esqueleto-3.5.10.3: Type-safe EDSL for SQL queries on persistent backends.

Safe Haskell | Safe-Inferred
Language | Haskell2010

Database.Esqueleto.Internal.Internal

Description

This is an internal module, anything exported by this module may change without a major version bump. Please use only Database.Esqueleto if possible.

If you use this module, please report what your use case is on the issue tracker so we can safely support it.

Synopsis

- fromStart :: forall a. (PersistEntity a, BackendCompatible SqlBackend (PersistEntityBackend a)) => SqlQuery (PreprocessedFrom (SqlExpr (Entity a)))
- newtype DBName = DBName {
  - unDBName :: Text
  }
- fromStartMaybe :: (PersistEntity a, BackendCompatible SqlBackend (PersistEntityBackend a)) => SqlQuery (PreprocessedFrom (SqlExpr (Maybe (Entity a))))
- fromJoin :: IsJoinKind join => PreprocessedFrom a -> PreprocessedFrom b -> SqlQuery (PreprocessedFrom (join a b))
- fromFinish :: PreprocessedFrom a -> SqlQuery a
- where_ :: SqlExpr (Value Bool) -> SqlQuery ()
- on :: SqlExpr (Value Bool) -> SqlQuery ()
- groupBy :: ToSomeValues a => a -> SqlQuery ()
- groupBy_ :: ToSomeValues a => a -> SqlQuery ()
- orderBy :: [SqlExpr OrderBy] -> SqlQuery ()
- asc :: PersistField a => SqlExpr (Value a) -> SqlExpr OrderBy
- desc :: PersistField a => SqlExpr (Value a) -> SqlExpr OrderBy
- orderByExpr :: Builder -> SqlExpr (Value a) -> SqlExpr OrderBy
- limit :: Int64 -> SqlQuery ()
- offset :: Int64 -> SqlQuery ()
- distinct :: SqlQuery a -> SqlQuery a
- distinctOn :: [SqlExpr DistinctOn] -> SqlQuery a -> SqlQuery a
- don :: SqlExpr (Value a) -> SqlExpr DistinctOn
- distinctOnOrderBy :: [SqlExpr OrderBy] -> SqlQuery a -> SqlQuery a
- rand :: SqlExpr OrderBy
- having :: SqlExpr (Value Bool) -> SqlQuery ()
- locking :: LockingKind -> SqlQuery ()
- putLocking :: LockingClause -> SqlQuery ()
- sub_select :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a)
- subSelect :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value (Maybe a))
- subSelectMaybe :: PersistField a => SqlQuery (SqlExpr (Value (Maybe a))) -> SqlExpr (Value (Maybe a))
- subSelectCount :: (Num a, PersistField a) => SqlQuery ignored -> SqlExpr (Value a)
- subSelectList :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (ValueList a)
- subSelectForeign :: (BackendCompatible SqlBackend (PersistEntityBackend val1), PersistEntity val1, PersistEntity val2, PersistField a) => SqlExpr (Entity val2) -> EntityField val2 (Key val1) -> (SqlExpr (Entity val1) -> SqlExpr (Value a)) -> SqlExpr (Value a)
- subSelectUnsafe :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a)
- (^.) :: forall typ val. (PersistEntity val, PersistField typ) => SqlExpr (Entity val) -> EntityField val typ -> SqlExpr (Value typ)
- withNonNull :: PersistField typ => SqlExpr (Value (Maybe typ)) -> (SqlExpr (Value typ) -> SqlQuery a) -> SqlQuery a
- (?.) :: (PersistEntity val, PersistField typ) => SqlExpr (Maybe (Entity val)) -> EntityField val typ -> SqlExpr (Value (Maybe typ))
- val :: PersistField typ => typ -> SqlExpr (Value typ)
- isNothing :: PersistField typ => SqlExpr (Value (Maybe typ)) -> SqlExpr (Value Bool)
- isNothing_ :: PersistField typ => SqlExpr (Value (Maybe typ)) -> SqlExpr (Value Bool)
- just :: SqlExpr (Value typ) -> SqlExpr (Value (Maybe typ))
- nothing :: SqlExpr (Value (Maybe typ))
- joinV :: SqlExpr (Value (Maybe (Maybe typ))) -> SqlExpr (Value (Maybe typ))
- countHelper :: Num a => Builder -> Builder -> SqlExpr (Value typ) -> SqlExpr (Value a)
- countRows :: Num a => SqlExpr (Value a)
- count :: Num a => SqlExpr (Value typ) -> SqlExpr (Value a)
- countDistinct :: Num a => SqlExpr (Value typ) -> SqlExpr (Value a)
- not_ :: SqlExpr (Value Bool) -> SqlExpr (Value Bool)
- (==.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (>=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (>.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (<=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (<.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (!=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool)
- (&&.) :: SqlExpr (Value Bool) -> SqlExpr (Value Bool) -> SqlExpr (Value Bool)
- (||.) :: SqlExpr (Value Bool) -> SqlExpr (Value Bool) -> SqlExpr (Value Bool)
- (+.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a)
- (-.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a)
- (/.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a)
- (*.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a)
- between :: PersistField a => SqlExpr (Value a) -> (SqlExpr (Value a), SqlExpr (Value a)) -> SqlExpr (Value Bool)
- random_ :: (PersistField a, Num a) => SqlExpr (Value a)
- round_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b)
- ceiling_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b)
- floor_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b)
- sum_ :: (PersistField a, PersistField b) => SqlExpr (Value a) -> SqlExpr (Value (Maybe b))
- min_ :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value (Maybe a))
- max_ :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value (Maybe a))
- avg_ :: (PersistField a, PersistField b) => SqlExpr (Value a) -> SqlExpr (Value (Maybe b))
- castNum :: (Num a, Num b) => SqlExpr (Value a) -> SqlExpr (Value b)
- castNumM :: (Num a, Num b) => SqlExpr (Value (Maybe a)) -> SqlExpr (Value (Maybe b))
- coalesce :: PersistField a => [SqlExpr (Value (Maybe a))] -> SqlExpr (Value (Maybe a))
- coalesceDefault :: PersistField a => [SqlExpr (Value (Maybe a))] -> SqlExpr (Value a) -> SqlExpr (Value a)
- lower_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- upper_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- trim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- rtrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- ltrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- length_ :: (SqlString s, Num a) => SqlExpr (Value s) -> SqlExpr (Value a)
- left_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s)
- right_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s)
- like :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool)
- ilike :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool)
- (%) :: SqlString s => SqlExpr (Value s)
- concat_ :: SqlString s => [SqlExpr (Value s)] -> SqlExpr (Value s)
- (++.) :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value s)
- castString :: (SqlString s, SqlString r) => SqlExpr (Value s) -> SqlExpr (Value r)
- subList_select :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (ValueList a)
- valList :: PersistField typ => [typ] -> SqlExpr (ValueList typ)
- justList :: SqlExpr (ValueList typ) -> SqlExpr (ValueList (Maybe typ))
- in_ :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (ValueList typ) -> SqlExpr (Value Bool)
- notIn :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (ValueList typ) -> SqlExpr (Value Bool)
- exists :: SqlQuery () -> SqlExpr (Value Bool)
- notExists :: SqlQuery () -> SqlExpr (Value Bool)
- set :: PersistEntity val => SqlExpr (Entity val) -> [SqlExpr (Entity val) -> SqlExpr Update] -> SqlQuery ()
- (=.) :: (PersistEntity val, PersistField typ) => EntityField val typ -> SqlExpr (Value typ) -> SqlExpr (Entity val) -> SqlExpr Update
- (+=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update
- (-=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update
- (*=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update
- (/=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update
- (<#) :: (a -> b) -> SqlExpr (Value a) -> SqlExpr (Insertion b)
- (<&>) :: SqlExpr (Insertion (a -> b)) -> SqlExpr (Value a) -> SqlExpr (Insertion b)
- case_ :: PersistField a => [(SqlExpr (Value Bool), SqlExpr (Value a))] -> SqlExpr (Value a) -> SqlExpr (Value a)
- toBaseId :: ToBaseId ent => SqlExpr (Value (Key ent)) -> SqlExpr (Value (Key (BaseEnt ent)))
- when_ :: expr (Value Bool) -> () -> expr a -> (expr (Value Bool), expr a)
- then_ :: ()
- else_ :: expr a -> expr a
- newtype Value a = Value {
  - unValue :: a
  }
- newtype ValueList a = ValueList a
- data SomeValue where
  - SomeValue :: SqlExpr (Value a) -> SomeValue
- class ToSomeValues a where
  - toSomeValues :: a -> [SomeValue]
- type family KnowResult a where ...
- class FinalResult a where
  - finalR :: a -> KnowResult a
- toUniqueDef :: forall a val. (KnowResult a ~ Unique val, PersistEntity val, FinalResult a) => a -> UniqueDef
- renderUpdates :: BackendCompatible SqlBackend backend => backend -> [SqlExpr (Entity val) -> SqlExpr Update] -> (Builder, [PersistValue])
- data InnerJoin a b = a `InnerJoin` b
- data CrossJoin a b = a `CrossJoin` b
- data LeftOuterJoin a b = a `LeftOuterJoin` b
- data RightOuterJoin a b = a `RightOuterJoin` b
- data FullOuterJoin a b = a `FullOuterJoin` b
- data JoinKind
  - = InnerJoinKind
  - | CrossJoinKind
  - | LeftOuterJoinKind
  - | RightOuterJoinKind
  - | FullOuterJoinKind
- class IsJoinKind join where
  - smartJoin :: a -> b -> join a b
  - reifyJoinKind :: join a b -> JoinKind
- data OnClauseWithoutMatchingJoinException = OnClauseWithoutMatchingJoinException String
- data OrderBy
- data DistinctOn
- data Update
- data Insertion a
- data a :& b = a :& b
- data LockingKind
  - = ForUpdate
  - | ForUpdateSkipLocked
  - | ForShare
  - | LockInShareMode
- data PostgresLockingKind = PostgresLockingKind {
  - postgresRowLevelLockStrength :: PostgresRowLevelLockStrength
  - postgresLockingOfClause :: Maybe LockingOfClause
  - postgresOnLockedBehavior :: OnLockedBehavior
  }
- data PostgresRowLevelLockStrength
  - = PostgresForUpdate
  - | PostgresForShare
- data LockingOfClause where
  - LockingOfClause :: LockableEntity a => a -> LockingOfClause
- data OnLockedBehavior
  - = NoWait
  - | SkipLocked
  - | Wait
- class LockableEntity a where
  - flattenLockableEntity :: a -> NonEmpty LockableSqlExpr
- makeLockableEntity :: LockableEntity a => IdentInfo -> a -> (Builder, [PersistValue])
- data LockableSqlExpr where
  - LockableSqlExpr :: PersistEntity val => SqlExpr (Entity val) -> LockableSqlExpr
- class PersistField a => SqlString a
- class ToBaseId ent where
  - type BaseEnt ent :: Type
  - toBaseIdWitness :: Key (BaseEnt ent) -> Key ent
- from :: From a => (a -> SqlQuery b) -> SqlQuery b
- class From a where
  - from_ :: SqlQuery a
- class FromPreprocess a where
  - fromPreprocess :: SqlQuery (PreprocessedFrom a)
- data EsqueletoError
  - = CompositeKeyErr CompositeKeyError
  - | AliasedValueErr UnexpectedValueError
  - | UnexpectedCaseErr UnexpectedCaseError
  - | SqlBinOpCompositeErr SqlBinOpCompositeError
- data UnexpectedValueError
  - = NotError
  - | ToInsertionError
  - | CombineInsertionError
  - | FoldHelpError
  - | SqlCaseError
  - | SqlCastAsError
  - | SqlFunctionError
  - | MakeOnClauseError
  - | MakeExcError
  - | MakeSetError
  - | MakeWhereError
  - | MakeHavingError
  - | FilterWhereAggError
  - | FilterWhereClauseError
- type CompositeKeyError = UnexpectedValueError
- data UnexpectedCaseError
  - = EmptySqlExprValueList
  - | MakeFromError
  - | UnsupportedSqlInsertIntoType
  - | InsertionFinalError
  - | NewIdentForError
  - | UnsafeSqlCaseError
  - | OperationNotSupported
  - | NotImplemented
- data SqlBinOpCompositeError
  - = MismatchingLengthsError
  - | NullPlaceholdersError
  - | DeconstructionError
- newtype SqlQuery a = Q {
  - unQ :: WriterT SideData (State IdentState) a
  }
- type SqlEntity ent = (PersistEntity ent, PersistEntityBackend ent ~ SqlBackend)
- data SideData = SideData {
  - sdDistinctClause :: !DistinctClause
  - sdFromClause :: ![FromClause]
  - sdSetClause :: ![SetClause]
  - sdWhereClause :: !WhereClause
  - sdGroupByClause :: !GroupByClause
  - sdHavingClause :: !HavingClause
  - sdOrderByClause :: ![OrderByClause]
  - sdLimitClause :: !LimitClause
  - sdLockingClause :: !LockingClause
  - sdCteClause :: ![CommonTableExpressionClause]
  }
- data DistinctClause
  - = DistinctAll
  - | DistinctStandard
  - | DistinctOn [SqlExpr DistinctOn]
- data FromClause
  - = FromStart Ident EntityDef
  - | FromJoin FromClause JoinKind FromClause (Maybe (SqlExpr (Value Bool)))
  - | OnClause (SqlExpr (Value Bool))
  - | FromRaw (NeedParens -> IdentInfo -> (Builder, [PersistValue]))
- data CommonTableExpressionKind
  - = RecursiveCommonTableExpression
  - | NormalCommonTableExpression
- data CommonTableExpressionClause = CommonTableExpressionClause CommonTableExpressionKind Ident (IdentInfo -> (Builder, [PersistValue]))
- data SubQueryType
  - = NormalSubQuery
  - | LateralSubQuery
- collectIdents :: FromClause -> Set Ident
- newtype SetClause = SetClause (SqlExpr Update)
- collectOnClauses :: SqlBackend -> [FromClause] -> Either (SqlExpr (Value Bool)) [FromClause]
- data WhereClause
  - = Where (SqlExpr (Value Bool))
  - | NoWhere
- newtype GroupByClause = GroupBy [SomeValue]
- type HavingClause = WhereClause
- type OrderByClause = SqlExpr OrderBy
- data LimitClause = Limit (Maybe Int64) (Maybe Int64)
- data LockingClause
  - = LegacyLockingClause LockingKind
  - | PostgresLockingClauses [PostgresLockingKind]
  - | NoLockingClause
- newtype Ident = I Text
- newtype IdentState = IdentState {
  - inUse :: HashSet Text
  }
- initialIdentState :: IdentState
- newIdentFor :: DBName -> SqlQuery Ident
- type IdentInfo = (SqlBackend, IdentState)
- useIdent :: IdentInfo -> Ident -> Builder
- data SqlExprMeta = SqlExprMeta {
  - sqlExprMetaCompositeFields :: Maybe (IdentInfo -> [Builder])
  - sqlExprMetaAlias :: Maybe Ident
  - sqlExprMetaIsReference :: Bool
  }
- noMeta :: SqlExprMeta
- hasCompositeKeyMeta :: SqlExprMeta -> Bool
- entityAsValue :: SqlExpr (Entity val) -> SqlExpr (Value (Entity val))
- entityAsValueMaybe :: SqlExpr (Maybe (Entity val)) -> SqlExpr (Value (Maybe (Entity val)))
- data SqlExpr a = ERaw SqlExprMeta (NeedParens -> IdentInfo -> (Builder, [PersistValue]))
- type SqlExprFunctorMessage = (('Text "You're trying to treat `SqlExpr` like a `Functor`, but it cannot be one." ':$$: 'Text "We would need to send arbitrary functions to the database for interpretation to support that instance.") ':$$: 'Text "See the docs for the fake instance of `Functor SqlExpr` for more information.") ':$$: 'Text "Consider using a SQL function with `unsafeSqlFunction` and a good type signature."
- data PreprocessedFrom a = PreprocessedFrom a FromClause
- data InsertFinal
- data NeedParens
  - = Parens
  - | Never
- parensM :: NeedParens -> Builder -> Builder
- data OrderByType
  - = ASC
  - | DESC
- fieldName :: (PersistEntity val, PersistField typ) => IdentInfo -> EntityField val typ -> Builder
- setAux :: (PersistEntity val, PersistField typ) => EntityField val typ -> (SqlExpr (Entity val) -> SqlExpr (Value typ)) -> SqlExpr (Entity val) -> SqlExpr Update
- sub :: PersistField a => Mode -> SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a)
- fromDBName :: IdentInfo -> DBName -> Builder
- existsHelper :: SqlQuery () -> SqlExpr (Value Bool)
- unsafeSqlCase :: PersistField a => [(SqlExpr (Value Bool), SqlExpr (Value a))] -> SqlExpr (Value a) -> SqlExpr (Value a)
- unsafeSqlBinOp :: Builder -> SqlExpr (Value a) -> SqlExpr (Value b) -> SqlExpr (Value c)
- unsafeSqlBinOpComposite :: Builder -> Builder -> SqlExpr (Value a) -> SqlExpr (Value b) -> SqlExpr (Value c)
- unsafeSqlValue :: Builder -> SqlExpr (Value a)
- unsafeSqlEntity :: PersistEntity ent => Ident -> SqlExpr (Entity ent)
- valueToFunctionArg :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue])
- unsafeSqlFunction :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b)
- unsafeSqlExtractSubField :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b)
- unsafeSqlFunctionParens :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b)
- unsafeSqlCastAs :: Text -> SqlExpr (Value a) -> SqlExpr (Value b)
- class UnsafeSqlFunctionArgument a where
  - toArgList :: a -> [SqlExpr (Value ())]
- veryUnsafeCoerceSqlExprValue :: SqlExpr (Value a) -> SqlExpr (Value b)
- veryUnsafeCoerceSqlExprValueList :: SqlExpr (ValueList a) -> SqlExpr (Value a)
- rawSelectSource :: (SqlSelect a r, MonadIO m1, MonadIO m2, SqlBackendCanRead backend) => Mode -> SqlQuery a -> ReaderT backend m1 (Acquire (ConduitT () r m2 ()))
- selectSource :: (SqlSelect a r, BackendCompatible SqlBackend backend, IsPersistBackend backend, PersistQueryRead backend, PersistStoreRead backend, PersistUniqueRead backend, MonadResource m) => SqlQuery a -> ConduitT () r (ReaderT backend m) ()
- select :: (SqlSelect a r, MonadIO m, SqlBackendCanRead backend) => SqlQuery a -> ReaderT backend m [r]
- selectOne :: (SqlSelect a r, MonadIO m, SqlBackendCanRead backend) => SqlQuery a -> ReaderT backend m (Maybe r)
- runSource :: Monad m => ConduitT () r (ReaderT backend m) () -> ReaderT backend m [r]
- rawEsqueleto :: (MonadIO m, SqlSelect a r, BackendCompatible SqlBackend backend) => Mode -> SqlQuery a -> ReaderT backend m Int64
- delete :: (MonadIO m, SqlBackendCanWrite backend) => SqlQuery () -> ReaderT backend m ()
- deleteCount :: (MonadIO m, SqlBackendCanWrite backend) => SqlQuery () -> ReaderT backend m Int64
- update :: (MonadIO m, PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val), SqlBackendCanWrite backend) => (SqlExpr (Entity val) -> SqlQuery ()) -> ReaderT backend m ()
- updateCount :: (MonadIO m, PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val), SqlBackendCanWrite backend) => (SqlExpr (Entity val) -> SqlQuery ()) -> ReaderT backend m Int64
- builderToText :: Builder -> Text
- toRawSql :: (SqlSelect a r, BackendCompatible SqlBackend backend) => Mode -> (backend, IdentState) -> SqlQuery a -> (Builder, [PersistValue])
- renderQueryToText :: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) => Mode -> SqlQuery a -> ReaderT backend m (Text, [PersistValue])
- renderQuerySelect :: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) => SqlQuery a -> ReaderT backend m (Text, [PersistValue])
- renderQueryDelete :: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) => SqlQuery a -> ReaderT backend m (Text, [PersistValue])
- renderQueryUpdate :: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) => SqlQuery a -> ReaderT backend m (Text, [PersistValue])
- renderQueryInsertInto :: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) => SqlQuery a -> ReaderT backend m (Text, [PersistValue])
- data Mode
  - = SELECT
  - | DELETE
  - | UPDATE
  - | INSERT_INTO
- uncommas :: [Builder] -> Builder
- intersperseB :: Builder -> [Builder] -> Builder
- uncommas' :: Monoid a => [(Builder, a)] -> (Builder, a)
- makeCte :: IdentInfo -> [CommonTableExpressionClause] -> (Builder, [PersistValue])
- makeInsertInto :: SqlSelect a r => IdentInfo -> Mode -> a -> (Builder, [PersistValue])
- makeSelect :: SqlSelect a r => IdentInfo -> Mode -> DistinctClause -> a -> (Builder, [PersistValue])
- makeFrom :: IdentInfo -> Mode -> [FromClause] -> (Builder, [PersistValue])
- makeSet :: IdentInfo -> [SetClause] -> (Builder, [PersistValue])
- makeWhere :: IdentInfo -> WhereClause -> (Builder, [PersistValue])
- makeGroupBy :: IdentInfo -> GroupByClause -> (Builder, [PersistValue])
- makeHaving :: IdentInfo -> WhereClause -> (Builder, [PersistValue])
- makeOrderByNoNewline :: IdentInfo -> [OrderByClause] -> (Builder, [PersistValue])
- makeOrderBy :: IdentInfo -> [OrderByClause] -> (Builder, [PersistValue])
- makeLimit :: IdentInfo -> LimitClause -> (Builder, [PersistValue])
- makeLocking :: IdentInfo -> LockingClause -> (Builder, [PersistValue])
- parens :: Builder -> Builder
- aliasedEntityColumnIdent :: Ident -> FieldDef -> Ident
- aliasedColumnName :: Ident -> IdentInfo -> Text -> Builder
- class SqlSelect a r | a -> r, r -> a where
  - sqlSelectCols :: IdentInfo -> a -> (Builder, [PersistValue])
  - sqlSelectColCount :: Proxy a -> Int
  - sqlSelectProcessRow :: [PersistValue] -> Either Text r
  - sqlInsertInto :: IdentInfo -> a -> (Builder, [PersistValue])
- unescapedColumnNames :: EntityDef -> [DBName]
- getEntityVal :: Proxy (SqlExpr (Entity a)) -> Proxy a
- materializeExpr :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue])
- from3P :: Proxy (a, b, c) -> Proxy ((a, b), c)
- from3 :: (a, b, c) -> ((a, b), c)
- to3 :: ((a, b), c) -> (a, b, c)
- from4P :: Proxy (a, b, c, d) -> Proxy ((a, b), (c, d))
- from4 :: (a, b, c, d) -> ((a, b), (c, d))
- to4 :: ((a, b), (c, d)) -> (a, b, c, d)
- from5P :: Proxy (a, b, c, d, e) -> Proxy ((a, b), (c, d), e)
- from5 :: (a, b, c, d, e) -> ((a, b), (c, d), e)
- to5 :: ((a, b), (c, d), e) -> (a, b, c, d, e)
- from6P :: Proxy (a, b, c, d, e, f) -> Proxy ((a, b), (c, d), (e, f))
- from6 :: (a, b, c, d, e, f) -> ((a, b), (c, d), (e, f))
- to6 :: ((a, b), (c, d), (e, f)) -> (a, b, c, d, e, f)
- from7P :: Proxy (a, b, c, d, e, f, g) -> Proxy ((a, b), (c, d), (e, f), g)
- from7 :: (a, b, c, d, e, f, g) -> ((a, b), (c, d), (e, f), g)
- to7 :: ((a, b), (c, d), (e, f), g) -> (a, b, c, d, e, f, g)
- from8P :: Proxy (a, b, c, d, e, f, g, h) -> Proxy ((a, b), (c, d), (e, f), (g, h))
- from8 :: (a, b, c, d, e, f, g, h) -> ((a, b), (c, d), (e, f), (g, h))
- to8 :: ((a, b), (c, d), (e, f), (g, h)) -> (a, b, c, d, e, f, g, h)
- from9P :: Proxy (a, b, c, d, e, f, g, h, i) -> Proxy ((a, b), (c, d), (e, f), (g, h), i)
- from9 :: (a, b, c, d, e, f, g, h, i) -> ((a, b), (c, d), (e, f), (g, h), i)
- to9 :: ((a, b), (c, d), (e, f), (g, h), i) -> (a, b, c, d, e, f, g, h, i)
- from10P :: Proxy (a, b, c, d, e, f, g, h, i, j) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j))
- from10 :: (a, b, c, d, e, f, g, h, i, j) -> ((a, b), (c, d), (e, f), (g, h), (i, j))
- to10 :: ((a, b), (c, d), (e, f), (g, h), (i, j)) -> (a, b, c, d, e, f, g, h, i, j)
- from11P :: Proxy (a, b, c, d, e, f, g, h, i, j, k) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), k)
- from11 :: (a, b, c, d, e, f, g, h, i, j, k) -> ((a, b), (c, d), (e, f), (g, h), (i, j), k)
- to11 :: ((a, b), (c, d), (e, f), (g, h), (i, j), k) -> (a, b, c, d, e, f, g, h, i, j, k)
- from12P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l))
- from12 :: (a, b, c, d, e, f, g, h, i, j, k, l) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l))
- to12 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l)) -> (a, b, c, d, e, f, g, h, i, j, k, l)
- from13P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m)
- from13 :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m)
- to13 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m)
- from14P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n))
- from14 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n))
- to14 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n)) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
- from15P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o)
- from15 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o)
- to15 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
- from16P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p))
- from16 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p))
- to16 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p)) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p)
- insertSelect :: (MonadIO m, PersistEntity a, SqlBackendCanWrite backend) => SqlQuery (SqlExpr (Insertion a)) -> ReaderT backend m ()
- insertSelectCount :: (MonadIO m, PersistEntity a, SqlBackendCanWrite backend) => SqlQuery (SqlExpr (Insertion a)) -> ReaderT backend m Int64
- renderExpr :: SqlBackend -> SqlExpr (Value Bool) -> Text
- data RenderExprException = RenderExprUnexpectedECompositeKey Text
- valkey :: (ToBackendKey SqlBackend entity, PersistField (Key entity)) => Int64 -> SqlExpr (Value (Key entity))
- valJ :: PersistField (Key entity) => Value (Key entity) -> SqlExpr (Value (Key entity))
- deleteKey :: (PersistStore backend, BaseBackend backend ~ PersistEntityBackend val, MonadIO m, PersistEntity val) => Key val -> ReaderT backend m ()
- associateJoin :: forall e1 e0. Ord (Key e0) => [(Entity e0, e1)] -> Map (Key e0) (e0, [e1])

# Documentation

fromStart :: forall a. (PersistEntity a, BackendCompatible SqlBackend (PersistEntityBackend a)) => SqlQuery (PreprocessedFrom (SqlExpr (Entity a))) Source #

(Internal) Start a `from` query with an entity. `from` does two kinds of magic using `fromStart`, `fromJoin` and `fromFinish`:

1. The simple but tedious magic of allowing tuples to be used.
2. The more advanced magic of creating `JOIN`s. The `JOIN` is processed from right to left. The rightmost entity of the `JOIN` is created with `fromStart`. Each `JOIN` step is then translated into a call to `fromJoin`. In the end, `fromFinish` is called to materialize the `JOIN`.

newtype DBName Source #

Copied from `persistent`

Constructors

DBName |

Fields

- unDBName :: Text

fromStartMaybe :: (PersistEntity a, BackendCompatible SqlBackend (PersistEntityBackend a)) => SqlQuery (PreprocessedFrom (SqlExpr (Maybe (Entity a)))) Source #

(Internal) Same as `fromStart`, but entity may be missing.

fromJoin :: IsJoinKind join => PreprocessedFrom a -> PreprocessedFrom b -> SqlQuery (PreprocessedFrom (join a b)) Source #

(Internal) Do a `JOIN`.

fromFinish :: PreprocessedFrom a -> SqlQuery a Source #

(Internal) Finish a `JOIN`.

where_ :: SqlExpr (Value Bool) -> SqlQuery () Source #

`WHERE` clause: restrict the query's result.

on :: SqlExpr (Value Bool) -> SqlQuery () Source #

An `ON` clause, useful to describe how two tables are related. Cross joins and tuple-joins do not need an `on` clause, but `InnerJoin` and the various outer joins do.

Database.Esqueleto.Experimental in version 4.0.0.0 of the library. The `Experimental` module has a dramatically improved means for introducing tables and entities that provides more power and less potential for runtime errors.

If you don't include an `on` clause (or include too many!) then a runtime exception will be thrown.

As an example, consider this simple join:

    select $
    from $ \(foo `InnerJoin` bar) -> do
      on (foo ^. FooId ==. bar ^. BarFooId)
      ...

We need to specify the clause for joining the two columns together. If we had this:

    select $
    from $ \(foo `CrossJoin` bar) -> do
      ...

Then we can safely omit the `on` clause, because the cross join will make pairs of all records possible.

You can do multiple `on` clauses in a query. This query joins three tables, and has two `on` clauses:

    select $
    from $ \(foo `InnerJoin` bar `InnerJoin` baz) -> do
      on (baz ^. BazId ==. bar ^. BarBazId)
      on (foo ^. FooId ==. bar ^. BarFooId)
      ...

Old versions of esqueleto required that you provide the `on` clauses in reverse order. This restriction has been lifted - you can now provide `on` clauses in any order, and the SQL should work itself out. The above query is now totally equivalent to this:

    select $
    from $ \(foo `InnerJoin` bar `InnerJoin` baz) -> do
      on (foo ^. FooId ==. bar ^. BarFooId)
      on (baz ^. BazId ==. bar ^. BarBazId)
      ...

groupBy :: ToSomeValues a => a -> SqlQuery () Source #

`GROUP BY` clause. You can enclose multiple columns in a tuple.

    select $ from \(foo `InnerJoin` bar) -> do
      on (foo ^. FooBarId ==. bar ^. BarId)
      groupBy (bar ^. BarId, bar ^. BarName)
      return (bar ^. BarId, bar ^. BarName, countRows)

With groupBy you can sort by aggregate functions, like so (we used `let` to restrict the more general `countRows` to `SqlSqlExpr (Value Int)` to avoid ambiguity---the second use of `countRows` has its type restricted by the `:: Int` below):

    r <- select $ from \(foo `InnerJoin` bar) -> do
      on (foo ^. FooBarId ==. bar ^. BarId)
      groupBy $ bar ^. BarName
      let countRows' = countRows
      orderBy [asc countRows']
      return (bar ^. BarName, countRows')
    forM_ r $ \(Value name, Value count) -> do
      print name
      print (count :: Int)

### Need more columns?

The `ToSomeValues` class is defined for `SqlExpr` and tuples of `SqlExpr`s. We only have definitions for up to 8 elements in a tuple right now, so it's possible that you may need to have more than 8 elements.

For example, consider a query with a `groupBy` call like this:

    groupBy (e0, e1, e2, e3, e4, e5, e6, e7)

This is the biggest you can get with a single tuple. However, you can easily nest the tuples to add more:

    groupBy ((e0, e1, e2, e3, e4, e5, e6, e7), e8, e9)

groupBy_ :: ToSomeValues a => a -> SqlQuery () Source #

An alias for `groupBy` that avoids conflict with the term from Data.List `groupBy`.

Since: 3.5.10.0

orderBy :: [SqlExpr OrderBy] -> SqlQuery () Source #

`ORDER BY` clause. See also `asc` and `desc`.

Multiple calls to `orderBy` get concatenated on the final query, including `distinctOnOrderBy`.

asc :: PersistField a => SqlExpr (Value a) -> SqlExpr OrderBy Source #

Ascending order of this field or SqlExpression.

desc :: PersistField a => SqlExpr (Value a) -> SqlExpr OrderBy Source #

Descending order of this field or SqlExpression.

orderByExpr :: Builder -> SqlExpr (Value a) -> SqlExpr OrderBy Source #

limit :: Int64 -> SqlQuery () Source #

`LIMIT`. Limit the number of returned rows.

offset :: Int64 -> SqlQuery () Source #

`OFFSET`. Usually used with `limit`.

distinct :: SqlQuery a -> SqlQuery a Source #

`DISTINCT`. Change the current `SELECT` into `SELECT DISTINCT`. For example:

    select $ distinct $
      from \foo -> do
      ...

Note that this also has the same effect:

    select $
      from \foo -> do
      distinct (return ())
      ...

Since: 2.2.4

distinctOn :: [SqlExpr DistinctOn] -> SqlQuery a -> SqlQuery a Source #

`DISTINCT ON`. Change the current `SELECT` into `SELECT DISTINCT ON (SqlExpressions)`. For example:

    select $
      from \foo ->
      distinctOn [don (foo ^. FooName), don (foo ^. FooState)] $ do
      ...

You can also chain different calls to `distinctOn`. The above is equivalent to:

    select $
      from \foo ->
      distinctOn [don (foo ^. FooName)] $
      distinctOn [don (foo ^. FooState)] $ do
      ...

Each call to `distinctOn` adds more SqlExpressions. Calls to `distinctOn` override any calls to `distinct`.

Note that PostgreSQL requires the SqlExpressions on `DISTINCT ON` to be the first ones to appear on a `ORDER BY`. This is not managed automatically by esqueleto, keeping its spirit of trying to be close to raw SQL.

Supported by PostgreSQL only.

Since: 2.2.4

don :: SqlExpr (Value a) -> SqlExpr DistinctOn Source #

Erase an SqlExpression's type so that it's suitable to be used by `distinctOn`.

Since: 2.2.4

distinctOnOrderBy :: [SqlExpr OrderBy] -> SqlQuery a -> SqlQuery a Source #

A convenience function that calls both `distinctOn` and `orderBy`. In other words,

    distinctOnOrderBy [asc foo, desc bar, desc quux] $ do
      ...

is the same as:

    distinctOn [don foo, don  bar, don  quux] $ do
      orderBy  [asc foo, desc bar, desc quux]
      ...

Since: 2.2.4

rand :: SqlExpr OrderBy Source #

Deprecated: Since 2.6.0: `rand` ordering function is not uniform across all databases! To avoid accidental partiality it will be removed in the next major version.

`ORDER BY random()` clause.

Since: 1.3.10

having :: SqlExpr (Value Bool) -> SqlQuery () Source #

`HAVING`.

Since: 1.2.2

locking :: LockingKind -> SqlQuery () Source #

Add a locking clause to the query. Please read `LockingKind` documentation and your RDBMS manual. Unsafe since not all locking clauses are implemented for every RDBMS

If multiple calls to `locking` are made on the same query, the last one is used.

Since: 2.2.7

putLocking :: LockingClause -> SqlQuery () Source #

Helper to add a any type of locking clause to a query

Since: 3.5.9.0

sub_select :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a) Source #

Deprecated: sub_select sub_select is an unsafe function to use. If used with a SqlQuery that returns 0 results, then it may return NULL despite not mentioning Maybe in the return type. If it returns more than 1 result, then it will throw a SQL error. Instead, consider using one of the following alternatives: - subSelect: attaches a LIMIT 1 and the Maybe return type, totally safe. - subSelectMaybe: Attaches a LIMIT 1, useful for a query that already has a Maybe in the return type. - subSelectCount: Performs a count of the query - this is always safe. - subSelectUnsafe: Performs no checks or guarantees. Safe to use with countRows and friends.

Execute a subquery `SELECT` in an SqlExpression. Returns a simple value so should be used only when the `SELECT` query is guaranteed to return just one row.

Deprecated in 3.2.0.

subSelect :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value (Maybe a)) Source #

Execute a subquery `SELECT` in a `SqlExpr`. The query passed to this function will only return a single result - it has a `LIMIT 1` passed in to the query to make it safe, and the return type is `Maybe` to indicate that the subquery might result in 0 rows.

If you find yourself writing ``joinV` . `subSelect``, then consider using `subSelectMaybe`.

If you're performing a `countRows`, then you can use `subSelectCount` which is safe.

If you know that the subquery will always return exactly one row (eg a foreign key constraint guarantees that you'll get exactly one row), then consider `subSelectUnsafe`, along with a comment explaining why it is safe.

Since: 3.2.0

subSelectMaybe :: PersistField a => SqlQuery (SqlExpr (Value (Maybe a))) -> SqlExpr (Value (Maybe a)) Source #

Execute a subquery `SELECT` in a `SqlExpr`. This function is a shorthand for the common ``joinV` . `subSelect`` idiom, where you are calling `subSelect` on an expression that would be `Maybe` already.

As an example, you would use this function when calling `sum_` or `max_`, which have `Maybe` in the result type (for a 0 row query).

Since: 3.2.0

subSelectCount :: (Num a, PersistField a) => SqlQuery ignored -> SqlExpr (Value a) Source #

Performs a `COUNT` of the given query in a `subSelect` manner. This is always guaranteed to return a result value, and is completely safe.

Since: 3.2.0

subSelectList :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (ValueList a) Source #

Execute a subquery `SELECT` in a `SqlExpr` that returns a list. This is an alias for `subList_select` and is provided for symmetry with the other safe subselect functions.

Since: 3.2.0

subSelectForeign Source #

Arguments

:: (BackendCompatible SqlBackend (PersistEntityBackend val1), PersistEntity val1, PersistEntity val2, PersistField a) |
=> SqlExpr (Entity val2) | An expression representing the table you have access to now.
-> EntityField val2 (Key val1) | The foreign key field on the table.
-> (SqlExpr (Entity val1) -> SqlExpr (Value a)) | A function to extract a value from the foreign reference table.
-> SqlExpr (Value a) |

Performs a sub-select using the given foreign key on the entity. This is useful to extract values that are known to be present by the database schema.

As an example, consider the following persistent definition:

    User
      profile ProfileId

    Profile
      name    Text

The following query will return the name of the user.

    getUserWithName =
        select $
        from $ user ->
        pure (user, subSelectForeign user UserProfile (^. ProfileName)

Since: 3.2.0

subSelectUnsafe :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a) Source #

Execute a subquery `SELECT` in a `SqlExpr`. This function is unsafe, because it can throw runtime exceptions in two cases:

1. If the query passed has 0 result rows, then it will return a `NULL` value. The `persistent` parsing operations will fail on an unexpected `NULL`.
2. If the query passed returns more than one row, then the SQL engine will fail with an error like "More than one row returned by a subquery used as an expression".

This function is safe if you guarantee that exactly one row will be returned, or if the result already has a `Maybe` type for some reason.

For variants with the safety encoded already, see `subSelect` and `subSelectMaybe`. For the most common safe use of this, see `subSelectCount`.

Since: 3.2.0

(^.) :: forall typ val. (PersistEntity val, PersistField typ) => SqlExpr (Entity val) -> EntityField val typ -> SqlExpr (Value typ) infixl 9 Source #

Project a field of an entity.

withNonNull :: PersistField typ => SqlExpr (Value (Maybe typ)) -> (SqlExpr (Value typ) -> SqlQuery a) -> SqlQuery a Source #

Project an SqlExpression that may be null, guarding against null cases.

(?.) :: (PersistEntity val, PersistField typ) => SqlExpr (Maybe (Entity val)) -> EntityField val typ -> SqlExpr (Value (Maybe typ)) Source #

Project a field of an entity that may be null.

val :: PersistField typ => typ -> SqlExpr (Value typ) Source #

Lift a constant value from Haskell-land to the query.

isNothing :: PersistField typ => SqlExpr (Value (Maybe typ)) -> SqlExpr (Value Bool) Source #

`IS NULL` comparison.

For `IS NOT NULL`, you can negate this with `not_`, as in `not_ (isNothing (person ^. PersonAge))`

Warning: Persistent and Esqueleto have different behavior for `!= Nothing`:

| Haskell | SQL
--- | --- | ---
Persistent | ``!=.` Nothing` | `IS NOT NULL`
Esqueleto | ``!=.` Nothing` | `!= NULL`

In SQL, `= NULL` and `!= NULL` return NULL instead of true or false. For this reason, you very likely do not want to use ``!=.` Nothing` in Esqueleto. You may find these `hlint` rules helpful to enforce this:

    - error: {lhs: v Database.Esqueleto.==. Database.Esqueleto.nothing, rhs: Database.Esqueleto.isNothing v, name: Use Esqueleto's isNothing}
    - error: {lhs: v Database.Esqueleto.==. Database.Esqueleto.val Nothing, rhs: Database.Esqueleto.isNothing v, name: Use Esqueleto's isNothing}
    - error: {lhs: v Database.Esqueleto.!=. Database.Esqueleto.nothing, rhs: not_ (Database.Esqueleto.isNothing v), name: Use Esqueleto's not isNothing}
    - error: {lhs: v Database.Esqueleto.!=. Database.Esqueleto.val Nothing, rhs: not_ (Database.Esqueleto.isNothing v), name: Use Esqueleto's not isNothing}

isNothing_ :: PersistField typ => SqlExpr (Value (Maybe typ)) -> SqlExpr (Value Bool) Source #

An alias for `isNothing` that avoids clashing with the function from Data.Maybe `isNothing`.

Since: 3.5.10.0

just :: SqlExpr (Value typ) -> SqlExpr (Value (Maybe typ)) Source #

Analogous to `Just`, promotes a value of type `typ` into one of type `Maybe typ`. It should hold that ``val` . Just === just . `val``.

nothing :: SqlExpr (Value (Maybe typ)) Source #

`NULL` value.

joinV :: SqlExpr (Value (Maybe (Maybe typ))) -> SqlExpr (Value (Maybe typ)) Source #

Join nested `Maybe`s in a `Value` into one. This is useful when calling aggregate functions on nullable fields.

countHelper :: Num a => Builder -> Builder -> SqlExpr (Value typ) -> SqlExpr (Value a) Source #

countRows :: Num a => SqlExpr (Value a) Source #

`COUNT(*)` value.

count :: Num a => SqlExpr (Value typ) -> SqlExpr (Value a) Source #

`COUNT`.

countDistinct :: Num a => SqlExpr (Value typ) -> SqlExpr (Value a) Source #

`COUNT(DISTINCT x)`.

Since: 2.4.1

not_ :: SqlExpr (Value Bool) -> SqlExpr (Value Bool) Source #

(==.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(>=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(>.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(<=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(<.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(!=.) :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (Value typ) -> SqlExpr (Value Bool) infix 4 Source #

(&&.) :: SqlExpr (Value Bool) -> SqlExpr (Value Bool) -> SqlExpr (Value Bool) infixr 3 Source #

(||.) :: SqlExpr (Value Bool) -> SqlExpr (Value Bool) -> SqlExpr (Value Bool) infixr 2 Source #

(+.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a) infixl 6 Source #

(-.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a) infixl 6 Source #

(/.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a) infixl 7 Source #

(*.) :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value a) infixl 7 Source #

between :: PersistField a => SqlExpr (Value a) -> (SqlExpr (Value a), SqlExpr (Value a)) -> SqlExpr (Value Bool) Source #

`BETWEEN`.

@since: 3.1.0

random_ :: (PersistField a, Num a) => SqlExpr (Value a) Source #

Deprecated: Since 2.6.0: `random_` is not uniform across all databases! Please use a specific one such as `random_`, `random_`, or `random_`

round_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b) Source #

ceiling_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b) Source #

floor_ :: (PersistField a, Num a, PersistField b, Num b) => SqlExpr (Value a) -> SqlExpr (Value b) Source #

sum_ :: (PersistField a, PersistField b) => SqlExpr (Value a) -> SqlExpr (Value (Maybe b)) Source #

min_ :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value (Maybe a)) Source #

max_ :: PersistField a => SqlExpr (Value a) -> SqlExpr (Value (Maybe a)) Source #

avg_ :: (PersistField a, PersistField b) => SqlExpr (Value a) -> SqlExpr (Value (Maybe b)) Source #

castNum :: (Num a, Num b) => SqlExpr (Value a) -> SqlExpr (Value b) Source #

Allow a number of one type to be used as one of another type via an implicit cast. An explicit cast is not made, this function changes only the types on the Haskell side.

Caveat: Trying to use `castNum` from `Double` to `Int` will not result in an integer, the original fractional number will still be used! Use `round_`, `ceiling_` or `floor_` instead.

Safety: This operation is mostly safe due to the `Num` constraint between the types and the fact that RDBMSs usually allow numbers of different types to be used interchangeably. However, there may still be issues with the query not being accepted by the RDBMS or `persistent` not being able to parse it.

Since: 2.2.9

castNumM :: (Num a, Num b) => SqlExpr (Value (Maybe a)) -> SqlExpr (Value (Maybe b)) Source #

Same as `castNum`, but for nullable values.

Since: 2.2.9

coalesce :: PersistField a => [SqlExpr (Value (Maybe a))] -> SqlExpr (Value (Maybe a)) Source #

`COALESCE` function. Evaluates the arguments in order and returns the value of the first non-NULL SqlExpression, or NULL (Nothing) otherwise. Some RDBMSs (such as SQLite) require at least two arguments; please refer to the appropriate documentation.

Since: 1.4.3

coalesceDefault :: PersistField a => [SqlExpr (Value (Maybe a))] -> SqlExpr (Value a) -> SqlExpr (Value a) Source #

Like `coalesce`, but takes a non-nullable SqlExpression placed at the end of the SqlExpression list, which guarantees a non-NULL result.

Since: 1.4.3

lower_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) Source #

`LOWER` function.

upper_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) Source #

`UPPER` function. @since 3.3.0

trim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) Source #

`TRIM` function. @since 3.3.0

rtrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) Source #

`RTRIM` function. @since 3.3.0

ltrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) Source #

`LTRIM` function. @since 3.3.0

length_ :: (SqlString s, Num a) => SqlExpr (Value s) -> SqlExpr (Value a) Source #

`LENGTH` function. @since 3.3.0

left_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s) Source #

`LEFT` function. @since 3.3.0

right_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s) Source #

`RIGHT` function. @since 3.3.0

like :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool) infixr 2 Source #

`LIKE` operator.

ilike :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool) infixr 2 Source #

`ILIKE` operator (case-insensitive `LIKE`).

Supported by PostgreSQL only.

Since: 2.2.3

(%) :: SqlString s => SqlExpr (Value s) Source #

The string ``%``. May be useful while using `like` and concatenation (`concat_` or `++.`, depending on your database). Note that you always have to type the parenthesis, for example:

    name `like` (%) ++. val "John" ++. (%)

concat_ :: SqlString s => [SqlExpr (Value s)] -> SqlExpr (Value s) Source #

The `CONCAT` function with a variable number of parameters. Supported by MySQL and PostgreSQL.

(++.) :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value s) infixr 5 Source #

The `||` string concatenation operator (named after Haskell's `++` in order to avoid naming clash with `||.`). Supported by SQLite and PostgreSQL.

castString :: (SqlString s, SqlString r) => SqlExpr (Value s) -> SqlExpr (Value r) Source #

Cast a string type into `Text`. This function is very useful if you want to use `newtype`s, or if you want to apply functions such as `like` to strings of different types.

Safety: This is a slightly unsafe function, especially if you have defined your own instances of `SqlString`. Also, since `Maybe` is an instance of `SqlString`, it's possible to turn a nullable value into a non-nullable one. Avoid using this function if possible.

subList_select :: PersistField a => SqlQuery (SqlExpr (Value a)) -> SqlExpr (ValueList a) Source #

Execute a subquery `SELECT` in an SqlExpression. Returns a list of values.

valList :: PersistField typ => [typ] -> SqlExpr (ValueList typ) Source #

Lift a list of constant value from Haskell-land to the query.

justList :: SqlExpr (ValueList typ) -> SqlExpr (ValueList (Maybe typ)) Source #

Same as `just` but for `ValueList`. Most of the time you won't need it, though, because you can use `just` from inside `subList_select` or `Just` from inside `valList`.

Since: 2.2.12

in_ :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (ValueList typ) -> SqlExpr (Value Bool) Source #

`IN` operator. For example if you want to select all `Person`s by a list of IDs:

    SELECT *
    FROM Person
    WHERE Person.id IN (?)

In `esqueleto`, we may write the same query above as:

    select $
    from $ \person -> do
    where_ $ person ^. PersonId `in_` valList personIds
    return person

Where `personIds` is of type `[Key Person]`.

notIn :: PersistField typ => SqlExpr (Value typ) -> SqlExpr (ValueList typ) -> SqlExpr (Value Bool) Source #

`NOT IN` operator.

exists :: SqlQuery () -> SqlExpr (Value Bool) Source #

`EXISTS` operator. For example:

    select $
    from $ \person -> do
    where_ $ exists $
             from $ \post -> do
             where_ (post ^. BlogPostAuthorId ==. person ^. PersonId)
    return person

notExists :: SqlQuery () -> SqlExpr (Value Bool) Source #

`NOT EXISTS` operator.

set :: PersistEntity val => SqlExpr (Entity val) -> [SqlExpr (Entity val) -> SqlExpr Update] -> SqlQuery () Source #

`SET` clause used on `UPDATE`s. Note that while it's not a type error to use this function on a `SELECT`, it will most certainly result in a runtime error.

(=.) :: (PersistEntity val, PersistField typ) => EntityField val typ -> SqlExpr (Value typ) -> SqlExpr (Entity val) -> SqlExpr Update infixr 3 Source #

(+=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update infixr 3 Source #

(-=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update infixr 3 Source #

(*=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update infixr 3 Source #

(/=.) :: (PersistEntity val, PersistField a) => EntityField val a -> SqlExpr (Value a) -> SqlExpr (Entity val) -> SqlExpr Update infixr 3 Source #

(<#) :: (a -> b) -> SqlExpr (Value a) -> SqlExpr (Insertion b) Source #

Apply a `PersistField` constructor to `SqlExpr Value` arguments.

(<&>) :: SqlExpr (Insertion (a -> b)) -> SqlExpr (Value a) -> SqlExpr (Insertion b) Source #

Apply extra `SqlExpr Value` arguments to a `PersistField` constructor

case_ :: PersistField a => [(SqlExpr (Value Bool), SqlExpr (Value a))] -> SqlExpr (Value a) -> SqlExpr (Value a) Source #

`CASE` statement. For example:

    select $
    return $
    case_
       [ when_
           (exists $
           from $ \p -> do
           where_ (p ^. PersonName ==. val "Mike"))
         then_
           (sub_select $
           from $ \v -> do
           let sub =
                   from $ \c -> do
                   where_ (c ^. PersonName ==. val "Mike")
                   return (c ^. PersonFavNum)
           where_ (v ^. PersonFavNum >. sub_select sub)
           return $ count (v ^. PersonName) +. val (1 :: Int)) ]
       (else_ $ val (-1))

This query is a bit complicated, but basically it checks if a person named `"Mike"` exists, and if that person does, run the subquery to find out how many people have a ranking (by Fav Num) higher than `"Mike"`.

NOTE: There are a few things to be aware about this statement.

- This only implements the full CASE statement, it does not implement the "simple" CASE statement.
- At least one `when_` and `then_` is mandatory otherwise it will emit an error.
- The `else_` is also mandatory, unlike the SQL statement in which if the `ELSE` is omitted it will return a `NULL`. You can reproduce this via `nothing`.

Since: 2.1.2

toBaseId :: ToBaseId ent => SqlExpr (Value (Key ent)) -> SqlExpr (Value (Key (BaseEnt ent))) Source #

Convert an entity's key into another entity's.

This function is to be used when you change an entity's `Id` to be that of another entity. For example:

    Bar
      barNum Int
    Foo
      bar BarId
      fooNum Int
      Primary bar

In this example, Bar is said to be the BaseEnt(ity), and Foo the child. To model this in Esqueleto, declare:

    instance ToBaseId Foo where
      type BaseEnt Foo = Bar
      toBaseIdWitness barId = FooKey barId

Now you're able to write queries such as:

    select $
    from $ (bar `InnerJoin` foo) -> do
    on (toBaseId (foo ^. FooId) ==. bar ^. BarId)
    return (bar, foo)

Note: this function may be unsafe to use in conditions not like the one of the example above.

Since: 2.4.3

when_ :: expr (Value Bool) -> () -> expr a -> (expr (Value Bool), expr a) Source #

Syntax sugar for `case_`.

Since: 2.1.2

then_ :: () Source #

Syntax sugar for `case_`.

Since: 2.1.2

else_ :: expr a -> expr a Source #

Syntax sugar for `case_`.

Since: 2.1.2

newtype Value a Source #

A single value (as opposed to a whole entity). You may use `(`^.`)` or `(`?.`)` to get a `Value` from an `Entity`.

Constructors

Value |

Fields

- unValue :: a

#### Instances

Instances details

Applicative Value Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods pure :: a -> Value a Source # (<*>) :: Value (a -> b) -> Value a -> Value b Source # liftA2 :: (a -> b -> c) -> Value a -> Value b -> Value c Source # (*>) :: Value a -> Value b -> Value b Source # (<*) :: Value a -> Value b -> Value a Source #
Functor Value Source # | Since: 1.4.4
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fmap :: (a -> b) -> Value a -> Value b Source # (<$) :: a -> Value b -> Value a Source #
Monad Value Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (>>=) :: Value a -> (a -> Value b) -> Value b Source # (>>) :: Value a -> Value b -> Value b Source # return :: a -> Value a Source #

(PersistEntity rec, PersistField typ, SymbolToField sym rec typ) => HasField (sym :: Symbol) (SqlExpr (Entity rec)) (SqlExpr (Value typ)) Source #

This instance allows you to use `record.field` notation with GHC 9.2's `OverloadedRecordDot` extension.

Example:

    -- persistent model:
    BlogPost
        authorId     PersonId
        title        Text

    -- query:
    select $ do
        bp <- from $ table @BlogPost
        pure $ bp.title

This is exactly equivalent to the following:

    blogPost :: SqlExpr (Entity BlogPost)

    blogPost ^. BlogPostTitle
    blogPost ^. #title
    blogPost.title

There's another instance defined on ``SqlExpr` (`Entity` (`Maybe` rec))`, which allows you to project from a `LEFT JOIN`ed entity.

Since: 3.5.4.0

Instance details Defined in Database.Esqueleto.Internal.Internal Methods getField :: SqlExpr (Entity rec) -> SqlExpr (Value typ) Source #

(PersistEntity rec, PersistField typ, SymbolToField sym rec typ) => HasField (sym :: Symbol) (SqlExpr (Maybe (Entity rec))) (SqlExpr (Value (Maybe typ))) Source #

This instance allows you to use `record.field` notation with GC 9.2's `OverloadedRecordDot` extension.

Example:

    -- persistent model:
    Person
        name         Text

    BlogPost
        title        Text
        authorId     PersonId

    -- query:

    select $ do
        (p :& bp) <- from $
            table Person
            leftJoin table BlogPost
            on do
                \(p :& bp) ->
                    just p.id ==. bp.authorId
        pure (p.name, bp.title)

The following forms are all equivalent:

    blogPost :: SqlExpr (Maybe (Entity BlogPost))

    blogPost ?. BlogPostTitle
    blogPost ?. #title
    blogPost.title

Since: 3.5.4.0

Instance details Defined in Database.Esqueleto.Internal.Internal Methods getField :: SqlExpr (Maybe (Entity rec)) -> SqlExpr (Value (Maybe typ)) Source #
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b, d ~ (a' :& b)) => DoInnerJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doInnerJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
(ToFrom a a', ToMaybe b, d ~ (a' :& ToMaybeT b), SqlSelect b r, ToAlias b, ToAliasReference b) => DoLeftJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doLeftJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
Show a => Show (Value a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> Value a -> ShowS Source # show :: Value a -> String Source # showList :: [Value a] -> ShowS Source #
ToAlias (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAlias Methods toAlias :: SqlExpr (Value a) -> SqlQuery (SqlExpr (Value a)) Source #
ToAliasReference (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAliasReference Methods toAliasReference :: Ident -> SqlExpr (Value a) -> SqlQuery (SqlExpr (Value a)) Source #
ToMaybe (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe Associated Types type ToMaybeT (SqlExpr (Value a)) Source # Methods toMaybe :: SqlExpr (Value a) -> ToMaybeT (SqlExpr (Value a)) Source #
ToSomeValues (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: SqlExpr (Value a) -> [SomeValue] Source #
Eq a => Eq (Value a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: Value a -> Value a -> Bool Source # (/=) :: Value a -> Value a -> Bool Source #
Ord a => Ord (Value a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods compare :: Value a -> Value a -> Ordering Source # (<) :: Value a -> Value a -> Bool Source # (<=) :: Value a -> Value a -> Bool Source # (>) :: Value a -> Value a -> Bool Source # (>=) :: Value a -> Value a -> Bool Source # max :: Value a -> Value a -> Value a Source # min :: Value a -> Value a -> Value a Source #
PersistField a => SqlSelect (SqlExpr (Value a)) (Value a) Source # | You may return any single value (i.e. a single column) from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Value a)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Value a) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source #
type ToMaybeT (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe type ToMaybeT (SqlExpr (Value a)) = SqlExpr (Value (Maybe (Nullable a)))

newtype ValueList a Source #

A list of single values. There's a limited set of functions able to work with this data type (such as `subList_select`, `valList`, `in_` and `exists`).

Constructors

ValueList a |

#### Instances

Instances details

Show a => Show (ValueList a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> ValueList a -> ShowS Source # show :: ValueList a -> String Source # showList :: [ValueList a] -> ShowS Source #
Eq a => Eq (ValueList a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: ValueList a -> ValueList a -> Bool Source # (/=) :: ValueList a -> ValueList a -> Bool Source #
Ord a => Ord (ValueList a) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

compare :: ValueList a -> ValueList a -> Ordering Source #

(<) :: ValueList a -> ValueList a -> Bool Source #

(<=) :: ValueList a -> ValueList a -> Bool Source #

(>) :: ValueList a -> ValueList a -> Bool Source #

(>=) :: ValueList a -> ValueList a -> Bool Source #

max :: ValueList a -> ValueList a -> ValueList a Source #

min :: ValueList a -> ValueList a -> ValueList a Source #

data SomeValue where Source #

A wrapper type for for any `expr (Value a)` for all a.

Constructors

SomeValue :: SqlExpr (Value a) -> SomeValue |

class ToSomeValues a where Source #

A class of things that can be converted into a list of SomeValue. It has instances for tuples and is the reason why `groupBy` can take tuples, like ``groupBy` (foo `^.` FooId, foo `^.` FooName, foo `^.` FooType)`.

Methods

toSomeValues :: a -> [SomeValue] Source #

#### Instances

Instances details

ToSomeValues (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: SqlExpr (Value a) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b) => ToSomeValues (a, b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c) => ToSomeValues (a, b, c) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c, ToSomeValues d) => ToSomeValues (a, b, c, d) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c, d) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c, ToSomeValues d, ToSomeValues e) => ToSomeValues (a, b, c, d, e) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c, d, e) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c, ToSomeValues d, ToSomeValues e, ToSomeValues f) => ToSomeValues (a, b, c, d, e, f) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c, d, e, f) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c, ToSomeValues d, ToSomeValues e, ToSomeValues f, ToSomeValues g) => ToSomeValues (a, b, c, d, e, f, g) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c, d, e, f, g) -> [SomeValue] Source #
(ToSomeValues a, ToSomeValues b, ToSomeValues c, ToSomeValues d, ToSomeValues e, ToSomeValues f, ToSomeValues g, ToSomeValues h) => ToSomeValues (a, b, c, d, e, f, g, h) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: (a, b, c, d, e, f, g, h) -> [SomeValue] Source #

type family KnowResult a where ... Source #

Equations

KnowResult (i -> o) = KnowResult o |
KnowResult a = a |

class FinalResult a where Source #

A class for constructors or function which result type is known.

Since: 3.1.3

Methods

finalR :: a -> KnowResult a Source #

#### Instances

Instances details

FinalResult (Unique val) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods finalR :: Unique val -> KnowResult (Unique val) Source #
FinalResult b => FinalResult (a -> b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods finalR :: (a -> b) -> KnowResult (a -> b) Source #

toUniqueDef :: forall a val. (KnowResult a ~ Unique val, PersistEntity val, FinalResult a) => a -> UniqueDef Source #

Convert a constructor for a `Unique` key on a record to the `UniqueDef` that defines it. You can supply just the constructor itself, or a value of the type - the library is capable of figuring it out from there.

Since: 3.1.3

renderUpdates :: BackendCompatible SqlBackend backend => backend -> [SqlExpr (Entity val) -> SqlExpr Update] -> (Builder, [PersistValue]) Source #

Render updates to be use in a SET clause for a given sql backend.

Since: 3.1.3

data InnerJoin a b infixl 2 Source #

Data type that represents an `INNER JOIN` (see `LeftOuterJoin` for an example).

Constructors

a `InnerJoin` b infixl 2 |

#### Instances

Instances details

IsJoinKind InnerJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> InnerJoin a b Source # reifyJoinKind :: InnerJoin a b -> JoinKind Source #
FromPreprocess (InnerJoin a b) => From (InnerJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (InnerJoin a b) Source #
(DoInnerJoin lateral lhs rhs r, lateral ~ IsLateral rhs) => ToFrom (InnerJoin lhs rhs) r Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: InnerJoin lhs rhs -> From r Source #

data CrossJoin a b infixl 2 Source #

Data type that represents a `CROSS JOIN` (see `LeftOuterJoin` for an example).

Constructors

a `CrossJoin` b infixl 2 |

#### Instances

Instances details

IsJoinKind CrossJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> CrossJoin a b Source # reifyJoinKind :: CrossJoin a b -> JoinKind Source #
FromPreprocess (CrossJoin a b) => From (CrossJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (CrossJoin a b) Source #
(DoCrossJoin lateral lhs rhs r, IsLateral rhs ~ lateral) => ToFrom (CrossJoin lhs rhs) r Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: CrossJoin lhs rhs -> From r Source #

data LeftOuterJoin a b infixl 2 Source #

Data type that represents a `LEFT OUTER JOIN`. For example,

    select $
    from $ \(person `LeftOuterJoin` pet) ->
      ...

is translated into

    SELECT ...
    FROM Person LEFT OUTER JOIN Pet
    ...

See also: `from`.

Constructors

a `LeftOuterJoin` b infixl 2 |

#### Instances

Instances details

IsJoinKind LeftOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> LeftOuterJoin a b Source # reifyJoinKind :: LeftOuterJoin a b -> JoinKind Source #
FromPreprocess (LeftOuterJoin a b) => From (LeftOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (LeftOuterJoin a b) Source #
(DoLeftJoin lateral lhs rhs r, lateral ~ IsLateral rhs) => ToFrom (LeftOuterJoin lhs rhs) r Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: LeftOuterJoin lhs rhs -> From r Source #

data RightOuterJoin a b infixl 2 Source #

Data type that represents a `RIGHT OUTER JOIN` (see `LeftOuterJoin` for an example).

Constructors

a `RightOuterJoin` b infixl 2 |

#### Instances

Instances details

IsJoinKind RightOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> RightOuterJoin a b Source # reifyJoinKind :: RightOuterJoin a b -> JoinKind Source #
FromPreprocess (RightOuterJoin a b) => From (RightOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (RightOuterJoin a b) Source #
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybeT a' ~ ma, HasOnClause rhs (ma :& b'), ErrorOnLateral b, rhs ~ (b, (ma :& b') -> SqlExpr (Value Bool))) => ToFrom (RightOuterJoin a rhs) (ma :& b') Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: RightOuterJoin a rhs -> From (ma :& b') Source #

data FullOuterJoin a b infixl 2 Source #

Data type that represents a `FULL OUTER JOIN` (see `LeftOuterJoin` for an example).

Constructors

a `FullOuterJoin` b infixl 2 |

#### Instances

Instances details

IsJoinKind FullOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> FullOuterJoin a b Source # reifyJoinKind :: FullOuterJoin a b -> JoinKind Source #
FromPreprocess (FullOuterJoin a b) => From (FullOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (FullOuterJoin a b) Source #
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybeT a' ~ ma, ToMaybe b', ToMaybeT b' ~ mb, HasOnClause rhs (ma :& mb), ErrorOnLateral b, rhs ~ (b, (ma :& mb) -> SqlExpr (Value Bool))) => ToFrom (FullOuterJoin a rhs) (ma :& mb) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: FullOuterJoin a rhs -> From (ma :& mb) Source #

data JoinKind Source #

(Internal) A kind of `JOIN`.

Constructors

InnerJoinKind

    INNER JOIN

CrossJoinKind

    CROSS JOIN

LeftOuterJoinKind

    LEFT OUTER JOIN

RightOuterJoinKind

    RIGHT OUTER JOIN

FullOuterJoinKind

    FULL OUTER JOIN

#### Instances

Instances details

Show JoinKind Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> JoinKind -> ShowS Source # show :: JoinKind -> String Source # showList :: [JoinKind] -> ShowS Source #
Eq JoinKind Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: JoinKind -> JoinKind -> Bool Source # (/=) :: JoinKind -> JoinKind -> Bool Source #

class IsJoinKind join where Source #

(Internal) Functions that operate on types (that should be) of kind `JoinKind`.

Methods

smartJoin :: a -> b -> join a b Source #

(Internal) `smartJoin a b` is a `JOIN` of the correct kind.

reifyJoinKind :: join a b -> JoinKind Source #

(Internal) Reify a `JoinKind` from a `JOIN`. This function is non-strict.

#### Instances

Instances details

IsJoinKind CrossJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> CrossJoin a b Source # reifyJoinKind :: CrossJoin a b -> JoinKind Source #
IsJoinKind FullOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> FullOuterJoin a b Source # reifyJoinKind :: FullOuterJoin a b -> JoinKind Source #
IsJoinKind InnerJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> InnerJoin a b Source # reifyJoinKind :: InnerJoin a b -> JoinKind Source #
IsJoinKind LeftOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> LeftOuterJoin a b Source # reifyJoinKind :: LeftOuterJoin a b -> JoinKind Source #
IsJoinKind RightOuterJoin Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods smartJoin :: a -> b -> RightOuterJoin a b Source # reifyJoinKind :: RightOuterJoin a b -> JoinKind Source #

data OnClauseWithoutMatchingJoinException Source #

Exception thrown whenever `on` is used to create an `ON` clause but no matching `JOIN` is found.

Constructors

OnClauseWithoutMatchingJoinException String |

#### Instances

Instances details

Exception OnClauseWithoutMatchingJoinException Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toException :: OnClauseWithoutMatchingJoinException -> SomeException Source # fromException :: SomeException -> Maybe OnClauseWithoutMatchingJoinException Source # displayException :: OnClauseWithoutMatchingJoinException -> String Source #
Show OnClauseWithoutMatchingJoinException Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> OnClauseWithoutMatchingJoinException -> ShowS Source # show :: OnClauseWithoutMatchingJoinException -> String Source # showList :: [OnClauseWithoutMatchingJoinException] -> ShowS Source #
Eq OnClauseWithoutMatchingJoinException Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source # (/=) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source #
Ord OnClauseWithoutMatchingJoinException Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

compare :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Ordering Source #

(<) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source #

(<=) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source #

(>) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source #

(>=) :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> Bool Source #

max :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException Source #

min :: OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException -> OnClauseWithoutMatchingJoinException Source #

data OrderBy Source #

Phantom type used by `orderBy`, `asc` and `desc`.

data DistinctOn Source #

Phantom type used by `distinctOn` and `don`.

data Update Source #

Phantom type for a `SET` operation on an entity of the given type (see `set` and `(=.)`).

data Insertion a Source #

Phantom type used by `insertSelect`.

#### Instances

Instances details

PersistEntity e => SqlSelect (SqlExpr (Insertion e)) (Insertion e) Source # | `INSERT INTO` hack.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Insertion e)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Insertion e) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source #

data a :& b infixl 2 Source #

A left-precedence pair. Pronounced "and". Used to represent expressions that have been joined together.

The precedence behavior can be demonstrated by:

    a :& b :& c == ((a :& b) :& c)

See the examples at the beginning of this module to see how this operator is used in `JOIN` operations.

Constructors

a :& b infixl 2 |

#### Instances

Instances details

(ToFrom a a', ToFrom b b') => DoCrossJoin NotLateral a b (a' :& b') Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doCrossJoin :: Proxy NotLateral -> a -> b -> From (a' :& b') Source #
(ToFrom a a', ToFrom b b', HasOnClause rhs (a' :& b'), rhs ~ (b, (a' :& b') -> SqlExpr (Value Bool))) => DoInnerJoin NotLateral a rhs (a' :& b') Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doInnerJoin :: Proxy NotLateral -> a -> rhs -> From (a' :& b') Source #
(ToFrom a a', ToFrom b b', ToMaybe b', ToMaybeT b' ~ mb, HasOnClause rhs (a' :& mb), rhs ~ (b, (a' :& mb) -> SqlExpr (Value Bool))) => DoLeftJoin NotLateral a rhs (a' :& mb) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doLeftJoin :: Proxy NotLateral -> a -> rhs -> From (a' :& mb) Source #
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b) => DoCrossJoin Lateral a (a' -> SqlQuery b) (a' :& b) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doCrossJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b) -> From (a' :& b) Source #
GetFirstTable t (t :& ts) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods getFirstTable :: (t :& ts) -> t Source #
GetFirstTable t ts => GetFirstTable t (ts :& x) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods getFirstTable :: (ts :& x) -> t Source #
GetFirstTable t (x :& t) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods getFirstTable :: (x :& t) -> t Source #
(Show a, Show b) => Show (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> (a :& b) -> ShowS Source # show :: (a :& b) -> String Source # showList :: [a :& b] -> ShowS Source #
(ToAlias a, ToAlias b) => ToAlias (a :& b) Source # | Identical to the tuple instance and provided for convenience. Since: 3.5.3.0
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toAlias :: (a :& b) -> SqlQuery (a :& b) Source #
(ToAliasReference a, ToAliasReference b) => ToAliasReference (a :& b) Source # | Identical to the tuple instance and provided for convenience. Since: 3.5.3.0
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toAliasReference :: Ident -> (a :& b) -> SqlQuery (a :& b) Source #
(ToMaybe a, ToMaybe b) => ToMaybe (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Associated Types type ToMaybeT (a :& b) Source # Methods toMaybe :: (a :& b) -> ToMaybeT (a :& b) Source #
(LockableEntity a, LockableEntity b) => LockableEntity (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods flattenLockableEntity :: (a :& b) -> NonEmpty LockableSqlExpr Source #
(Eq a, Eq b) => Eq (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: (a :& b) -> (a :& b) -> Bool Source # (/=) :: (a :& b) -> (a :& b) -> Bool Source #
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybeT a' ~ ma, ToMaybe b', ToMaybeT b' ~ mb, HasOnClause rhs (ma :& mb), ErrorOnLateral b, rhs ~ (b, (ma :& mb) -> SqlExpr (Value Bool))) => ToFrom (FullOuterJoin a rhs) (ma :& mb) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: FullOuterJoin a rhs -> From (ma :& mb) Source #
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybeT a' ~ ma, HasOnClause rhs (ma :& b'), ErrorOnLateral b, rhs ~ (b, (ma :& b') -> SqlExpr (Value Bool))) => ToFrom (RightOuterJoin a rhs) (ma :& b') Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods toFrom :: RightOuterJoin a rhs -> From (ma :& b') Source #
(SqlSelect a ra, SqlSelect b rb) => SqlSelect (a :& b) (ra :& rb) Source # | You may return joined values from a `select` query - this is identical to the tuple instance, but is provided for convenience. Since: 3.5.2.0
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods sqlSelectCols :: IdentInfo -> (a :& b) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a :& b) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra :& rb) Source # sqlInsertInto :: IdentInfo -> (a :& b) -> (Builder, [PersistValue]) Source #
type ToMaybeT (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join type ToMaybeT (a :& b) = ToMaybeT a :& ToMaybeT b

data LockingKind Source #

Different kinds of locking clauses supported by `locking`.

Note that each RDBMS has different locking support. The constructors of this datatype specify only the syntax of the locking mechanism, not its semantics. For example, even though both MySQL and PostgreSQL support `ForUpdate`, there are no guarantees that they will behave the same.

Since: 2.2.7

Constructors

ForUpdate | `FOR UPDATE` syntax. Supported by MySQL, Oracle and PostgreSQL. Since: 2.2.7
ForUpdateSkipLocked | `FOR UPDATE SKIP LOCKED` syntax. Supported by MySQL, Oracle and PostgreSQL. Since: 2.2.7
ForShare | `FOR SHARE` syntax. Supported by PostgreSQL. Since: 2.2.7
LockInShareMode | `LOCK IN SHARE MODE` syntax. Supported by MySQL. Since: 2.2.7

data PostgresLockingKind Source #

Postgres specific locking, used only internally

Since: 3.5.9.0

Constructors

PostgresLockingKind |

Fields

- postgresRowLevelLockStrength :: PostgresRowLevelLockStrength
- postgresLockingOfClause :: Maybe LockingOfClause
- postgresOnLockedBehavior :: OnLockedBehavior

data PostgresRowLevelLockStrength Source #

Constructors

PostgresForUpdate |
PostgresForShare |

#### Instances

Instances details

Eq PostgresRowLevelLockStrength Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source # (/=) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source #
Ord PostgresRowLevelLockStrength Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

compare :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Ordering Source #

(<) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source #

(<=) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source #

(>) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source #

(>=) :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> Bool Source #

max :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength Source #

min :: PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength -> PostgresRowLevelLockStrength Source #

data LockingOfClause where Source #

Constructors

LockingOfClause :: LockableEntity a => a -> LockingOfClause |

data OnLockedBehavior Source #

Constructors

NoWait | `NOWAIT` syntax locking behaviour. query excutes immediately failing on locked rows Since: 3.5.9.0
SkipLocked | `SKIP LOCKED` syntax locking behaviour. query skips locked rows Since: 3.5.9.0
Wait | default locking behaviour. query will wait on locked rows Since: 3.5.9.0

#### Instances

Instances details

Show OnLockedBehavior Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> OnLockedBehavior -> ShowS Source # show :: OnLockedBehavior -> String Source # showList :: [OnLockedBehavior] -> ShowS Source #
Eq OnLockedBehavior Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source # (/=) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source #
Ord OnLockedBehavior Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

compare :: OnLockedBehavior -> OnLockedBehavior -> Ordering Source #

(<) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source #

(<=) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source #

(>) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source #

(>=) :: OnLockedBehavior -> OnLockedBehavior -> Bool Source #

max :: OnLockedBehavior -> OnLockedBehavior -> OnLockedBehavior Source #

min :: OnLockedBehavior -> OnLockedBehavior -> OnLockedBehavior Source #

class LockableEntity a where Source #

Lockable entity

Example use:

    select $ do
        (p :& bp) <- from $
            table Person
            innerJoin table BlogPost
                on do
                    (p :& bp) -> p ^. PersonId ==. b ^. BlogPostAuthorId
        forUpdateOf (p :& b) skipLocked
        return p

Methods

flattenLockableEntity :: a -> NonEmpty LockableSqlExpr Source #

#### Instances

Instances details

PersistEntity val => LockableEntity (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods flattenLockableEntity :: SqlExpr (Entity val) -> NonEmpty LockableSqlExpr Source #
(LockableEntity a, LockableEntity b) => LockableEntity (a :& b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods flattenLockableEntity :: (a :& b) -> NonEmpty LockableSqlExpr Source #

makeLockableEntity :: LockableEntity a => IdentInfo -> a -> (Builder, [PersistValue]) Source #

data LockableSqlExpr where Source #

Constructors

LockableSqlExpr :: PersistEntity val => SqlExpr (Entity val) -> LockableSqlExpr |

class PersistField a => SqlString a Source #

Phantom class of data types that are treated as strings by the RDBMS. It has no methods because it's only used to avoid type errors such as trying to concatenate integers.

If you have a custom data type or `newtype`, feel free to make it an instance of this class.

Since: 2.4.0

#### Instances

Instances details

SqlString Html Source # | Since: 2.3.0
Instance details Defined in Database.Esqueleto.Internal.Internal
SqlString ByteString Source # | Since: 2.3.0
Instance details Defined in Database.Esqueleto.Internal.Internal
SqlString Text Source # | Since: 2.3.0
Instance details Defined in Database.Esqueleto.Internal.Internal
SqlString Text Source # | Since: 2.3.0
Instance details Defined in Database.Esqueleto.Internal.Internal
SqlString a => SqlString (Maybe a) Source # | Since: 2.4.0
Instance details Defined in Database.Esqueleto.Internal.Internal
a ~ Char => SqlString [a] Source # | Since: 2.3.0
Instance details Defined in Database.Esqueleto.Internal.Internal

class ToBaseId ent where Source #

Class that enables one to use `toBaseId` to convert an entity's key on a query into another (cf. `toBaseId`).

Associated Types

type BaseEnt ent :: Type Source #

e.g. `type BaseEnt MyBase = MyChild`

Methods

toBaseIdWitness :: Key (BaseEnt ent) -> Key ent Source #

Convert from the key of the BaseEnt(ity) to the key of the child entity. This function is not actually called, but that it typechecks proves this operation is safe.

from :: From a => (a -> SqlQuery b) -> SqlQuery b Source #

`FROM` clause: bring entities into scope.

Note that this function will be replaced by the one in Database.Esqueleto.Experimental in version 4.0.0.0 of the library. The `Experimental` module has a dramatically improved means for introducing tables and entities that provides more power and less potential for runtime errors.

This function internally uses two type classes in order to provide some flexibility of how you may call it. Internally we refer to these type classes as the two different magics.

The innermost magic allows you to use `from` with the following types:

- `expr (Entity val)`, which brings a single entity into scope.
- `expr (Maybe (Entity val))`, which brings a single entity that may be `NULL` into scope. Used for `OUTER JOIN`s.
- A `JOIN` of any other two types allowed by the innermost magic, where a `JOIN` may be an `InnerJoin`, a `CrossJoin`, a `LeftOuterJoin`, a `RightOuterJoin`, or a `FullOuterJoin`. The `JOINs` have left fixity.

The outermost magic allows you to use `from` on any tuples of types supported by innermost magic (and also tuples of tuples, and so on), up to 8-tuples.

Note that using `from` for the same entity twice does work and corresponds to a self-join. You don't even need to use two different calls to `from`, you may use a `JOIN` or a tuple.

The following are valid examples of uses of `from` (the types of the arguments of the lambda are inside square brackets):

    from $ \person -> ...
    from $ \(person, blogPost) -> ...
    from $ \(p `LeftOuterJoin` mb) -> ...
    from $ \(p1 `InnerJoin` f `InnerJoin` p2) -> ...
    from $ \((p1 `InnerJoin` f) `InnerJoin` p2) -> ...

The types of the arguments to the lambdas above are, respectively:

    person
      :: ( Esqueleto query expr backend
         , PersistEntity Person
         , PersistEntityBackend Person ~ backend
         ) => expr (Entity Person)
    (person, blogPost)
      :: (...) => (expr (Entity Person), expr (Entity BlogPost))
    (p `LeftOuterJoin` mb)
      :: (...) => InnerJoin (expr (Entity Person)) (expr (Maybe (Entity BlogPost)))
    (p1 `InnerJoin` f `InnerJoin` p2)
      :: (...) => InnerJoin
                    (InnerJoin (expr (Entity Person))
                               (expr (Entity Follow)))
                    (expr (Entity Person))
    (p1 `InnerJoin` (f `InnerJoin` p2)) ::
      :: (...) => InnerJoin
                    (expr (Entity Person))
                    (InnerJoin (expr (Entity Follow))
                               (expr (Entity Person)))

Note that some backends may not support all kinds of `JOIN`s.

class From a where Source #

(Internal) Class that implements the tuple `from` magic (see `fromStart`).

Methods

from_ :: SqlQuery a Source #

#### Instances

Instances details

FromPreprocess (SqlExpr (Entity val)) => From (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (SqlExpr (Entity val)) Source #
FromPreprocess (SqlExpr (Maybe (Entity val))) => From (SqlExpr (Maybe (Entity val))) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (SqlExpr (Maybe (Entity val))) Source #
FromPreprocess (CrossJoin a b) => From (CrossJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (CrossJoin a b) Source #
FromPreprocess (FullOuterJoin a b) => From (FullOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (FullOuterJoin a b) Source #
FromPreprocess (InnerJoin a b) => From (InnerJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (InnerJoin a b) Source #
FromPreprocess (LeftOuterJoin a b) => From (LeftOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (LeftOuterJoin a b) Source #
FromPreprocess (RightOuterJoin a b) => From (RightOuterJoin a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (RightOuterJoin a b) Source #
(From a, From b) => From (a, b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b) Source #
(From a, From b, From c) => From (a, b, c) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c) Source #
(From a, From b, From c, From d) => From (a, b, c, d) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c, d) Source #
(From a, From b, From c, From d, From e) => From (a, b, c, d, e) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c, d, e) Source #
(From a, From b, From c, From d, From e, From f) => From (a, b, c, d, e, f) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c, d, e, f) Source #
(From a, From b, From c, From d, From e, From f, From g) => From (a, b, c, d, e, f, g) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c, d, e, f, g) Source #
(From a, From b, From c, From d, From e, From f, From g, From h) => From (a, b, c, d, e, f, g, h) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (a, b, c, d, e, f, g, h) Source #

class FromPreprocess a where Source #

(Internal) Class that implements the `JOIN` `from` magic (see `fromStart`).

Methods

fromPreprocess :: SqlQuery (PreprocessedFrom a) Source #

#### Instances

Instances details

(PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val)) => FromPreprocess (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fromPreprocess :: SqlQuery (PreprocessedFrom (SqlExpr (Entity val))) Source #
(PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val)) => FromPreprocess (SqlExpr (Maybe (Entity val))) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fromPreprocess :: SqlQuery (PreprocessedFrom (SqlExpr (Maybe (Entity val)))) Source #
(FromPreprocess a, FromPreprocess b, IsJoinKind join) => FromPreprocess (join a b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fromPreprocess :: SqlQuery (PreprocessedFrom (join a b)) Source #

data EsqueletoError Source #

Exception data type for `esqueleto` internal errors

Constructors

CompositeKeyErr CompositeKeyError |
AliasedValueErr UnexpectedValueError |
UnexpectedCaseErr UnexpectedCaseError |
SqlBinOpCompositeErr SqlBinOpCompositeError |

#### Instances

Instances details

Exception EsqueletoError Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toException :: EsqueletoError -> SomeException Source # fromException :: SomeException -> Maybe EsqueletoError Source # displayException :: EsqueletoError -> String Source #
Show EsqueletoError Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> EsqueletoError -> ShowS Source # show :: EsqueletoError -> String Source # showList :: [EsqueletoError] -> ShowS Source #

data UnexpectedValueError Source #

Constructors

NotError |
ToInsertionError |
CombineInsertionError |
FoldHelpError |
SqlCaseError |
SqlCastAsError |
SqlFunctionError |
MakeOnClauseError |
MakeExcError |
MakeSetError |
MakeWhereError |
MakeHavingError |
FilterWhereAggError |
FilterWhereClauseError |

#### Instances

Instances details

Show UnexpectedValueError Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> UnexpectedValueError -> ShowS Source # show :: UnexpectedValueError -> String Source # showList :: [UnexpectedValueError] -> ShowS Source #

type CompositeKeyError = UnexpectedValueError Source #

data UnexpectedCaseError Source #

Constructors

EmptySqlExprValueList |
MakeFromError |
UnsupportedSqlInsertIntoType |
InsertionFinalError |
NewIdentForError |
UnsafeSqlCaseError |
OperationNotSupported |
NotImplemented |

#### Instances

Instances details

Show UnexpectedCaseError Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> UnexpectedCaseError -> ShowS Source # show :: UnexpectedCaseError -> String Source # showList :: [UnexpectedCaseError] -> ShowS Source #

data SqlBinOpCompositeError Source #

Constructors

MismatchingLengthsError |
NullPlaceholdersError |
DeconstructionError |

#### Instances

Instances details

Show SqlBinOpCompositeError Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> SqlBinOpCompositeError -> ShowS Source # show :: SqlBinOpCompositeError -> String Source # showList :: [SqlBinOpCompositeError] -> ShowS Source #

newtype SqlQuery a Source #

SQL backend for `esqueleto` using `SqlPersistT`.

Constructors

Q |

Fields

- unQ :: WriterT SideData (State IdentState) a

#### Instances

Instances details

Applicative SqlQuery Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods pure :: a -> SqlQuery a Source # (<*>) :: SqlQuery (a -> b) -> SqlQuery a -> SqlQuery b Source # liftA2 :: (a -> b -> c) -> SqlQuery a -> SqlQuery b -> SqlQuery c Source # (*>) :: SqlQuery a -> SqlQuery b -> SqlQuery b Source # (<*) :: SqlQuery a -> SqlQuery b -> SqlQuery a Source #
Functor SqlQuery Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fmap :: (a -> b) -> SqlQuery a -> SqlQuery b Source # (<$) :: a -> SqlQuery b -> SqlQuery a Source #
Monad SqlQuery Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (>>=) :: SqlQuery a -> (a -> SqlQuery b) -> SqlQuery b Source # (>>) :: SqlQuery a -> SqlQuery b -> SqlQuery b Source # return :: a -> SqlQuery a Source #
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b, d ~ (a' :& b)) => DoInnerJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doInnerJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
(ToFrom a a', ToMaybe b, d ~ (a' :& ToMaybeT b), SqlSelect b r, ToAlias b, ToAliasReference b) => DoLeftJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doLeftJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b) => DoCrossJoin Lateral a (a' -> SqlQuery b) (a' :& b) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doCrossJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b) -> From (a' :& b) Source #
(SqlSelect a r, ToAlias a, ToAliasReference a) => ToFrom (SubQuery (SqlQuery a)) a Source # |
Instance details Defined in Database.Esqueleto.Experimental.From Methods toFrom :: SubQuery (SqlQuery a) -> From a Source #
(SqlSelect a r, ToAlias a, ToAliasReference a) => ToFrom (SqlQuery a) a Source # |
Instance details Defined in Database.Esqueleto.Experimental.From Methods toFrom :: SqlQuery a -> From a Source #
(SqlSelect a r, ToAlias a, ToAliasReference a) => ToSqlSetOperation (SqlQuery a) a Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.SqlSetOperation Methods toSqlSetOperation :: SqlQuery a -> SqlSetOperation a Source #
ValidOnClause (a -> SqlQuery b) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join

type SqlEntity ent = (PersistEntity ent, PersistEntityBackend ent ~ SqlBackend) Source #

Constraint synonym for `persistent` entities whose backend is `SqlBackend`.

data SideData Source #

Side data written by `SqlQuery`.

Constructors

SideData |

Fields

- sdDistinctClause :: !DistinctClause
- sdFromClause :: ![FromClause]
- sdSetClause :: ![SetClause]
- sdWhereClause :: !WhereClause
- sdGroupByClause :: !GroupByClause
- sdHavingClause :: !HavingClause
- sdOrderByClause :: ![OrderByClause]
- sdLimitClause :: !LimitClause
- sdLockingClause :: !LockingClause
- sdCteClause :: ![CommonTableExpressionClause]

#### Instances

Instances details

Monoid SideData Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: SideData Source # mappend :: SideData -> SideData -> SideData Source # mconcat :: [SideData] -> SideData Source #
Semigroup SideData Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: SideData -> SideData -> SideData Source # sconcat :: NonEmpty SideData -> SideData Source # stimes :: Integral b => b -> SideData -> SideData Source #

data DistinctClause Source #

The `DISTINCT` "clause".

Constructors

DistinctAll | The default, everything.
DistinctStandard | Only `DISTINCT`, SQL standard.
DistinctOn [SqlExpr DistinctOn] | `DISTINCT ON`, PostgreSQL extension.

#### Instances

Instances details

Monoid DistinctClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: DistinctClause Source # mappend :: DistinctClause -> DistinctClause -> DistinctClause Source # mconcat :: [DistinctClause] -> DistinctClause Source #
Semigroup DistinctClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: DistinctClause -> DistinctClause -> DistinctClause Source # sconcat :: NonEmpty DistinctClause -> DistinctClause Source # stimes :: Integral b => b -> DistinctClause -> DistinctClause Source #

data FromClause Source #

A part of a `FROM` clause.

Constructors

FromStart Ident EntityDef |
FromJoin FromClause JoinKind FromClause (Maybe (SqlExpr (Value Bool))) |
OnClause (SqlExpr (Value Bool)) |
FromRaw (NeedParens -> IdentInfo -> (Builder, [PersistValue])) |

#### Instances

Instances details

Show FromClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> FromClause -> ShowS Source # show :: FromClause -> String Source # showList :: [FromClause] -> ShowS Source #

data CommonTableExpressionKind Source #

Constructors

RecursiveCommonTableExpression |
NormalCommonTableExpression |

#### Instances

Instances details

Eq CommonTableExpressionKind Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: CommonTableExpressionKind -> CommonTableExpressionKind -> Bool Source # (/=) :: CommonTableExpressionKind -> CommonTableExpressionKind -> Bool Source #

data CommonTableExpressionClause Source #

Constructors

CommonTableExpressionClause CommonTableExpressionKind Ident (IdentInfo -> (Builder, [PersistValue])) |

data SubQueryType Source #

Constructors

NormalSubQuery |
LateralSubQuery |

#### Instances

Instances details

Show SubQueryType Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> SubQueryType -> ShowS Source # show :: SubQueryType -> String Source # showList :: [SubQueryType] -> ShowS Source #

collectIdents :: FromClause -> Set Ident Source #

newtype SetClause Source #

A part of a `SET` clause.

Constructors

SetClause (SqlExpr Update) |

collectOnClauses :: SqlBackend -> [FromClause] -> Either (SqlExpr (Value Bool)) [FromClause] Source #

Collect `OnClause`s on `FromJoin`s. Returns the first unmatched `OnClause`s data on error. Returns a list without `OnClauses` on success.

data WhereClause Source #

A complete `WHERE` clause.

Constructors

Where (SqlExpr (Value Bool)) |
NoWhere |

#### Instances

Instances details

Monoid WhereClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: WhereClause Source # mappend :: WhereClause -> WhereClause -> WhereClause Source # mconcat :: [WhereClause] -> WhereClause Source #
Semigroup WhereClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: WhereClause -> WhereClause -> WhereClause Source # sconcat :: NonEmpty WhereClause -> WhereClause Source # stimes :: Integral b => b -> WhereClause -> WhereClause Source #

newtype GroupByClause Source #

A `GROUP BY` clause.

Constructors

GroupBy [SomeValue] |

#### Instances

Instances details

Monoid GroupByClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: GroupByClause Source # mappend :: GroupByClause -> GroupByClause -> GroupByClause Source # mconcat :: [GroupByClause] -> GroupByClause Source #
Semigroup GroupByClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: GroupByClause -> GroupByClause -> GroupByClause Source # sconcat :: NonEmpty GroupByClause -> GroupByClause Source # stimes :: Integral b => b -> GroupByClause -> GroupByClause Source #

type HavingClause = WhereClause Source #

A `HAVING` cause.

type OrderByClause = SqlExpr OrderBy Source #

A `ORDER BY` clause.

data LimitClause Source #

A `LIMIT` clause.

Constructors

Limit (Maybe Int64) (Maybe Int64) |

#### Instances

Instances details

Monoid LimitClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: LimitClause Source # mappend :: LimitClause -> LimitClause -> LimitClause Source # mconcat :: [LimitClause] -> LimitClause Source #
Semigroup LimitClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: LimitClause -> LimitClause -> LimitClause Source # sconcat :: NonEmpty LimitClause -> LimitClause Source # stimes :: Integral b => b -> LimitClause -> LimitClause Source #
Eq LimitClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: LimitClause -> LimitClause -> Bool Source # (/=) :: LimitClause -> LimitClause -> Bool Source #

data LockingClause Source #

A locking clause.

Constructors

LegacyLockingClause LockingKind | Locking clause not specific to any database implementation
PostgresLockingClauses [PostgresLockingKind] | Locking clause specific to postgres
NoLockingClause |

#### Instances

Instances details

Monoid LockingClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods mempty :: LockingClause Source # mappend :: LockingClause -> LockingClause -> LockingClause Source # mconcat :: [LockingClause] -> LockingClause Source #
Semigroup LockingClause Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (<>) :: LockingClause -> LockingClause -> LockingClause Source # sconcat :: NonEmpty LockingClause -> LockingClause Source # stimes :: Integral b => b -> LockingClause -> LockingClause Source #

newtype Ident Source #

Identifier used for table names.

Constructors

I Text |

#### Instances

Instances details

Show Ident Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> Ident -> ShowS Source # show :: Ident -> String Source # showList :: [Ident] -> ShowS Source #
Eq Ident Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: Ident -> Ident -> Bool Source # (/=) :: Ident -> Ident -> Bool Source #
Ord Ident Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods compare :: Ident -> Ident -> Ordering Source # (<) :: Ident -> Ident -> Bool Source # (<=) :: Ident -> Ident -> Bool Source # (>) :: Ident -> Ident -> Bool Source # (>=) :: Ident -> Ident -> Bool Source # max :: Ident -> Ident -> Ident Source # min :: Ident -> Ident -> Ident Source #

newtype IdentState Source #

List of identifiers already in use and supply of temporary identifiers.

Constructors

IdentState |

Fields

- inUse :: HashSet Text

initialIdentState :: IdentState Source #

newIdentFor :: DBName -> SqlQuery Ident Source #

Create a fresh `Ident`. If possible, use the given `DBName`.

type IdentInfo = (SqlBackend, IdentState) Source #

Information needed to escape and use identifiers.

useIdent :: IdentInfo -> Ident -> Builder Source #

Use an identifier.

data SqlExprMeta Source #

Constructors

SqlExprMeta |

Fields

- sqlExprMetaCompositeFields :: Maybe (IdentInfo -> [Builder])
- sqlExprMetaAlias :: Maybe Ident
- sqlExprMetaIsReference :: Bool

noMeta :: SqlExprMeta Source #

Empty `SqlExprMeta` if you are constructing an `ERaw` probably use this for your meta

hasCompositeKeyMeta :: SqlExprMeta -> Bool Source #

Does this meta contain values for composite fields. This field is field out for composite key values

entityAsValue :: SqlExpr (Entity val) -> SqlExpr (Value (Entity val)) Source #

entityAsValueMaybe :: SqlExpr (Maybe (Entity val)) -> SqlExpr (Value (Maybe (Entity val))) Source #

data SqlExpr a Source #

An expression on the SQL backend.

Raw expression: Contains a `SqlExprMeta` and a function for building the expr. It recieves a parameter telling it whether it is in a parenthesized context, and takes information about the SQL connection (mainly for escaping names) and returns both an string (`Builder`) and a list of values to be interpolated by the SQL backend.

Constructors

ERaw SqlExprMeta (NeedParens -> IdentInfo -> (Builder, [PersistValue])) |

#### Instances

Instances details

(TypeError SqlExprFunctorMessage :: Constraint) => Functor SqlExpr Source #

Folks often want the ability to promote a Haskell function into the `SqlExpr` expression language - and naturally reach for `fmap`. Unfortunately, this is impossible. We cannot send *functions* to the database, which is what we would need to do in order for this to make sense. Let's consider the type of `fmap` for `SqlExpr`:

    fmap :: (a -> b) -> SqlExpr a -> SqlExpr b

This type signature is making a pretty strong claim: "Give me a Haskell function from `a -> b`. I will then transform a SQL expression representing a Haskell value of type `a` and turn it into a SQL expression representing a Haskell value of type `b`."

Let's suppose we *could* do this - `fmap (+1)` would have to somehow inspect the function expression means "add one", and then translate that to the appropriate SQL.

This is why `esqueleto` defines a bunch of operators: `x `+.` (`val` 1)` can be used instead of ``fmap` (+1) x`.

If you do have a SQL function, then you can provide a safe type and introduce it with `unsafeSqlFunction` or `unsafeSqlBinOp`.

Since: 3.5.8.2

Instance details Defined in Database.Esqueleto.Internal.Internal Methods fmap :: (a -> b) -> SqlExpr a -> SqlExpr b Source # (<$) :: a -> SqlExpr b -> SqlExpr a Source #

(PersistEntity rec, PersistField typ, SymbolToField sym rec typ) => HasField (sym :: Symbol) (SqlExpr (Entity rec)) (SqlExpr (Value typ)) Source #

This instance allows you to use `record.field` notation with GHC 9.2's `OverloadedRecordDot` extension.

Example:

    -- persistent model:
    BlogPost
        authorId     PersonId
        title        Text

    -- query:
    select $ do
        bp <- from $ table @BlogPost
        pure $ bp.title

This is exactly equivalent to the following:

    blogPost :: SqlExpr (Entity BlogPost)

    blogPost ^. BlogPostTitle
    blogPost ^. #title
    blogPost.title

There's another instance defined on ``SqlExpr` (`Entity` (`Maybe` rec))`, which allows you to project from a `LEFT JOIN`ed entity.

Since: 3.5.4.0

Instance details Defined in Database.Esqueleto.Internal.Internal Methods getField :: SqlExpr (Entity rec) -> SqlExpr (Value typ) Source #

(PersistEntity rec, PersistField typ, SymbolToField sym rec typ) => HasField (sym :: Symbol) (SqlExpr (Maybe (Entity rec))) (SqlExpr (Value (Maybe typ))) Source #

This instance allows you to use `record.field` notation with GC 9.2's `OverloadedRecordDot` extension.

Example:

    -- persistent model:
    Person
        name         Text

    BlogPost
        title        Text
        authorId     PersonId

    -- query:

    select $ do
        (p :& bp) <- from $
            table Person
            leftJoin table BlogPost
            on do
                \(p :& bp) ->
                    just p.id ==. bp.authorId
        pure (p.name, bp.title)

The following forms are all equivalent:

    blogPost :: SqlExpr (Maybe (Entity BlogPost))

    blogPost ?. BlogPostTitle
    blogPost ?. #title
    blogPost.title

Since: 3.5.4.0

Instance details Defined in Database.Esqueleto.Internal.Internal Methods getField :: SqlExpr (Maybe (Entity rec)) -> SqlExpr (Value (Maybe typ)) Source #
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b, d ~ (a' :& b)) => DoInnerJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doInnerJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
(ToFrom a a', ToMaybe b, d ~ (a' :& ToMaybeT b), SqlSelect b r, ToAlias b, ToAliasReference b) => DoLeftJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d Source # |
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods doLeftJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d Source #
ToAlias (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAlias Methods toAlias :: SqlExpr (Value a) -> SqlQuery (SqlExpr (Value a)) Source #
ToAlias (SqlExpr (Entity a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAlias Methods toAlias :: SqlExpr (Entity a) -> SqlQuery (SqlExpr (Entity a)) Source #
ToAlias (SqlExpr (Maybe (Entity a))) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAlias Methods toAlias :: SqlExpr (Maybe (Entity a)) -> SqlQuery (SqlExpr (Maybe (Entity a))) Source #
ToAliasReference (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAliasReference Methods toAliasReference :: Ident -> SqlExpr (Value a) -> SqlQuery (SqlExpr (Value a)) Source #
ToAliasReference (SqlExpr (Entity a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAliasReference Methods toAliasReference :: Ident -> SqlExpr (Entity a) -> SqlQuery (SqlExpr (Entity a)) Source #
ToAliasReference (SqlExpr (Maybe (Entity a))) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToAliasReference Methods toAliasReference :: Ident -> SqlExpr (Maybe (Entity a)) -> SqlQuery (SqlExpr (Maybe (Entity a))) Source #
ToMaybe (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe Associated Types type ToMaybeT (SqlExpr (Value a)) Source # Methods toMaybe :: SqlExpr (Value a) -> ToMaybeT (SqlExpr (Value a)) Source #
ToMaybe (SqlExpr (Entity a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe Associated Types type ToMaybeT (SqlExpr (Entity a)) Source # Methods toMaybe :: SqlExpr (Entity a) -> ToMaybeT (SqlExpr (Entity a)) Source #
ToMaybe (SqlExpr (Maybe a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe Associated Types type ToMaybeT (SqlExpr (Maybe a)) Source # Methods toMaybe :: SqlExpr (Maybe a) -> ToMaybeT (SqlExpr (Maybe a)) Source #
FromPreprocess (SqlExpr (Entity val)) => From (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (SqlExpr (Entity val)) Source #
FromPreprocess (SqlExpr (Maybe (Entity val))) => From (SqlExpr (Maybe (Entity val))) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods from_ :: SqlQuery (SqlExpr (Maybe (Entity val))) Source #
(PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val)) => FromPreprocess (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fromPreprocess :: SqlQuery (PreprocessedFrom (SqlExpr (Entity val))) Source #
(PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val)) => FromPreprocess (SqlExpr (Maybe (Entity val))) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods fromPreprocess :: SqlQuery (PreprocessedFrom (SqlExpr (Maybe (Entity val)))) Source #
PersistEntity val => LockableEntity (SqlExpr (Entity val)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods flattenLockableEntity :: SqlExpr (Entity val) -> NonEmpty LockableSqlExpr Source #
ToSomeValues (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toSomeValues :: SqlExpr (Value a) -> [SomeValue] Source #
a ~ Value b => UnsafeSqlFunctionArgument (SqlExpr a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: SqlExpr a -> [SqlExpr (Value ())] Source #
PersistEntity ent => ToFrom (Table ent) (SqlExpr (Entity ent)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.From Methods toFrom :: Table ent -> From (SqlExpr (Entity ent)) Source #
PersistEntity e => SqlSelect (SqlExpr (Insertion e)) (Insertion e) Source # | `INSERT INTO` hack.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Insertion e)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Insertion e) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source #
PersistField a => SqlSelect (SqlExpr (Value a)) (Value a) Source # | You may return any single value (i.e. a single column) from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Value a)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Value a) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source #
PersistEntity a => SqlSelect (SqlExpr (Entity a)) (Entity a) Source # | You may return an `Entity` from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Entity a) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Entity a)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Entity a) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Entity a) -> (Builder, [PersistValue]) Source #
PersistEntity a => SqlSelect (SqlExpr (Maybe (Entity a))) (Maybe (Entity a)) Source # | You may return a possibly-`NULL` `Entity` from a `select` query.

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> SqlExpr (Maybe (Entity a)) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (SqlExpr (Maybe (Entity a))) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (Maybe (Entity a)) Source #

sqlInsertInto :: IdentInfo -> SqlExpr (Maybe (Entity a)) -> (Builder, [PersistValue]) Source #

type ToMaybeT (SqlExpr (Value a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe type ToMaybeT (SqlExpr (Value a)) = SqlExpr (Value (Maybe (Nullable a)))
type ToMaybeT (SqlExpr (Entity a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe type ToMaybeT (SqlExpr (Entity a)) = SqlExpr (Maybe (Entity a))
type ToMaybeT (SqlExpr (Maybe a)) Source # |
Instance details Defined in Database.Esqueleto.Experimental.ToMaybe type ToMaybeT (SqlExpr (Maybe a)) = SqlExpr (Maybe a)

type SqlExprFunctorMessage = (('Text "You're trying to treat `SqlExpr` like a `Functor`, but it cannot be one." ':$$: 'Text "We would need to send arbitrary functions to the database for interpretation to support that instance.") ':$$: 'Text "See the docs for the fake instance of `Functor SqlExpr` for more information.") ':$$: 'Text "Consider using a SQL function with `unsafeSqlFunction` and a good type signature." Source #

The type error message given when you try to do `fmap` on a `SqlExpr`. This is intended to guide folks towards the docs, which should guide them towards alternative implementations.

Since: 3.5.8.2

data PreprocessedFrom a Source #

Data type to support from hack

Constructors

PreprocessedFrom a FromClause |

data InsertFinal Source #

Phantom type used to mark a `INSERT INTO` query.

data NeedParens Source #

Constructors

Parens |
Never |

#### Instances

Instances details

Eq NeedParens Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods (==) :: NeedParens -> NeedParens -> Bool Source # (/=) :: NeedParens -> NeedParens -> Bool Source #

parensM :: NeedParens -> Builder -> Builder Source #

data OrderByType Source #

Constructors

ASC |
DESC |

fieldName :: (PersistEntity val, PersistField typ) => IdentInfo -> EntityField val typ -> Builder Source #

setAux :: (PersistEntity val, PersistField typ) => EntityField val typ -> (SqlExpr (Entity val) -> SqlExpr (Value typ)) -> SqlExpr (Entity val) -> SqlExpr Update Source #

sub :: PersistField a => Mode -> SqlQuery (SqlExpr (Value a)) -> SqlExpr (Value a) Source #

fromDBName :: IdentInfo -> DBName -> Builder Source #

existsHelper :: SqlQuery () -> SqlExpr (Value Bool) Source #

unsafeSqlCase :: PersistField a => [(SqlExpr (Value Bool), SqlExpr (Value a))] -> SqlExpr (Value a) -> SqlExpr (Value a) Source #

(Internal) Create a case statement.

Since: 2.1.1

unsafeSqlBinOp :: Builder -> SqlExpr (Value a) -> SqlExpr (Value b) -> SqlExpr (Value c) Source #

(Internal) Create a custom binary operator. You should not use this function directly since its type is very general, you should always use it with an explicit type signature. For example:

    (==.) :: SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value Bool)
    (==.) = unsafeSqlBinOp " = "

In the example above, we constraint the arguments to be of the same type and constraint the result to be a boolean value.

unsafeSqlBinOpComposite :: Builder -> Builder -> SqlExpr (Value a) -> SqlExpr (Value b) -> SqlExpr (Value c) Source #

Similar to `unsafeSqlBinOp`, but may also be applied to composite keys. Uses the operator given as the second argument whenever applied to composite keys.

Usage example:

    (==.) :: SqlExpr (Value a) -> SqlExpr (Value a) -> SqlExpr (Value Bool)
    (==.) = unsafeSqlBinOpComposite " = " " AND "

Persistent has a hack for implementing composite keys (see `ECompositeKey` doc for more details), so we're forced to use a hack here as well. We deconstruct `ERaw` values based on two rules:

- If it is a single placeholder, then it's assumed to be coming from a `PersistList` and thus its components are separated so that they may be applied to a composite key.
- If it is not a single placeholder, then it's assumed to be a foreign (composite or not) key, so we enforce that it has no placeholders and split it on the commas.

unsafeSqlValue :: Builder -> SqlExpr (Value a) Source #

(Internal) A raw SQL value. The same warning from `unsafeSqlBinOp` applies to this function as well.

unsafeSqlEntity :: PersistEntity ent => Ident -> SqlExpr (Entity ent) Source #

valueToFunctionArg :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source #

unsafeSqlFunction :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b) Source #

(Internal) A raw SQL function. Once again, the same warning from `unsafeSqlBinOp` applies to this function as well.

unsafeSqlExtractSubField :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b) Source #

(Internal) An unsafe SQL function to extract a subfield from a compound field, e.g. datetime. See `unsafeSqlBinOp` for warnings.

Since: 1.3.6.

unsafeSqlFunctionParens :: UnsafeSqlFunctionArgument a => Builder -> a -> SqlExpr (Value b) Source #

(Internal) A raw SQL function. Preserves parentheses around arguments. See `unsafeSqlBinOp` for warnings.

unsafeSqlCastAs :: Text -> SqlExpr (Value a) -> SqlExpr (Value b) Source #

(Internal) An explicit SQL type cast using CAST(value as type). See `unsafeSqlBinOp` for warnings.

class UnsafeSqlFunctionArgument a where Source #

(Internal) This class allows `unsafeSqlFunction` to work with different numbers of arguments; specifically it allows providing arguments to a sql function via an n-tuple of `SqlExpr (Value _)` values, which are not all necessarily required to be the same type. There are instances for up to 10-tuples, but for sql functions which take more than 10 arguments, you can also nest tuples, as e.g. `toArgList ((a,b),(c,d))` is the same as `toArgList (a,b,c,d)`.

Methods

toArgList :: a -> [SqlExpr (Value ())] Source #

#### Instances

Instances details

UnsafeSqlFunctionArgument () Source # | Useful for 0-argument functions, like `now` in Postgresql. Since: 3.2.1
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: () -> [SqlExpr (Value ())] Source #
a ~ Value b => UnsafeSqlFunctionArgument (SqlExpr a) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: SqlExpr a -> [SqlExpr (Value ())] Source #
UnsafeSqlFunctionArgument a => UnsafeSqlFunctionArgument [a] Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: [a] -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b) => UnsafeSqlFunctionArgument (a, b) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c) => UnsafeSqlFunctionArgument (a, b, c) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d) => UnsafeSqlFunctionArgument (a, b, c, d) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e) => UnsafeSqlFunctionArgument (a, b, c, d, e) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e, UnsafeSqlFunctionArgument f) => UnsafeSqlFunctionArgument (a, b, c, d, e, f) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e, f) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e, UnsafeSqlFunctionArgument f, UnsafeSqlFunctionArgument g) => UnsafeSqlFunctionArgument (a, b, c, d, e, f, g) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e, f, g) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e, UnsafeSqlFunctionArgument f, UnsafeSqlFunctionArgument g, UnsafeSqlFunctionArgument h) => UnsafeSqlFunctionArgument (a, b, c, d, e, f, g, h) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e, f, g, h) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e, UnsafeSqlFunctionArgument f, UnsafeSqlFunctionArgument g, UnsafeSqlFunctionArgument h, UnsafeSqlFunctionArgument i) => UnsafeSqlFunctionArgument (a, b, c, d, e, f, g, h, i) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e, f, g, h, i) -> [SqlExpr (Value ())] Source #
(UnsafeSqlFunctionArgument a, UnsafeSqlFunctionArgument b, UnsafeSqlFunctionArgument c, UnsafeSqlFunctionArgument d, UnsafeSqlFunctionArgument e, UnsafeSqlFunctionArgument f, UnsafeSqlFunctionArgument g, UnsafeSqlFunctionArgument h, UnsafeSqlFunctionArgument i, UnsafeSqlFunctionArgument j) => UnsafeSqlFunctionArgument (a, b, c, d, e, f, g, h, i, j) Source # | Since: 3.2.3
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toArgList :: (a, b, c, d, e, f, g, h, i, j) -> [SqlExpr (Value ())] Source #

veryUnsafeCoerceSqlExprValue :: SqlExpr (Value a) -> SqlExpr (Value b) Source #

(Internal) Coerce a value's type from 'SqlExpr (Value a)' to 'SqlExpr (Value b)'. You should not use this function unless you know what you're doing!

veryUnsafeCoerceSqlExprValueList :: SqlExpr (ValueList a) -> SqlExpr (Value a) Source #

(Internal) Coerce a value's type from 'SqlExpr (ValueList a)' to 'SqlExpr (Value a)'. Does not work with empty lists.

rawSelectSource :: (SqlSelect a r, MonadIO m1, MonadIO m2, SqlBackendCanRead backend) => Mode -> SqlQuery a -> ReaderT backend m1 (Acquire (ConduitT () r m2 ())) Source #

(Internal) Execute an `esqueleto` `SELECT` `SqlQuery` inside `persistent`'s `SqlPersistT` monad.

selectSource :: (SqlSelect a r, BackendCompatible SqlBackend backend, IsPersistBackend backend, PersistQueryRead backend, PersistStoreRead backend, PersistUniqueRead backend, MonadResource m) => SqlQuery a -> ConduitT () r (ReaderT backend m) () Source #

Execute an `esqueleto` `SELECT` query inside `persistent`'s `SqlPersistT` monad and return a `Source` of rows.

select :: (SqlSelect a r, MonadIO m, SqlBackendCanRead backend) => SqlQuery a -> ReaderT backend m [r] Source #

Execute an `esqueleto` `SELECT` query inside `persistent`'s `SqlPersistT` monad and return a list of rows.

We've seen that `from` has some magic about which kinds of things you may bring into scope. This `select` function also has some magic for which kinds of things you may bring back to Haskell-land by using `SqlQuery`'s `return`:

- You may return a `SqlExpr (`Entity` v)` for an entity `v` (i.e., like the `*` in SQL), which is then returned to Haskell-land as just `Entity v`.
- You may return a `SqlExpr (Maybe (Entity v))` for an entity `v` that may be `NULL`, which is then returned to Haskell-land as `Maybe (Entity v)`. Used for `OUTER JOIN`s.
- You may return a `SqlExpr (`Value` t)` for a value `t` (i.e., a single column), where `t` is any instance of `PersistField`, which is then returned to Haskell-land as `Value t`. You may use `Value` to return projections of an `Entity` (see `(`^.`)` and `(`?.`)`) or to return any other value calculated on the query (e.g., `countRows` or `subSelect`).

The `SqlSelect a r` class has functional dependencies that allow type information to flow both from `a` to `r` and vice-versa. This means that you'll almost never have to give any type signatures for `esqueleto` queries. For example, the query ``select` $ from $ \p -> return p` alone is ambiguous, but in the context of

    do ps <- select $
             from $ \p ->
             return p
       liftIO $ mapM_ (putStrLn . personName . entityVal) ps

we are able to infer from that single `personName . entityVal` function composition that the `p` inside the query is of type `SqlExpr (Entity Person)`.

selectOne :: (SqlSelect a r, MonadIO m, SqlBackendCanRead backend) => SqlQuery a -> ReaderT backend m (Maybe r) Source #

Execute an `esqueleto` `SELECT` query inside `persistent`'s `SqlPersistT` monad and return the first entry wrapped in a `Maybe`. @since 3.5.1.0

### Example usage

Expand

    firstPerson :: MonadIO m => SqlPersistT m (Maybe (Entity Person))
    firstPerson =
     selectOne $ do
         person <- from $ table @Person
         return person

The above query is equivalent to a `select` combined with `limit` but you would still have to transform the results from a list:

    firstPerson :: MonadIO m => SqlPersistT m [Entity Person]
    firstPerson =
     select $ do
         person <- from $ table @Person
         limit 1
         return person

runSource :: Monad m => ConduitT () r (ReaderT backend m) () -> ReaderT backend m [r] Source #

(Internal) Run a `Source` of rows.

rawEsqueleto :: (MonadIO m, SqlSelect a r, BackendCompatible SqlBackend backend) => Mode -> SqlQuery a -> ReaderT backend m Int64 Source #

(Internal) Execute an `esqueleto` statement inside `persistent`'s `SqlPersistT` monad.

delete :: (MonadIO m, SqlBackendCanWrite backend) => SqlQuery () -> ReaderT backend m () Source #

Execute an `esqueleto` `DELETE` query inside `persistent`'s `SqlPersistT` monad. Note that currently there are no type checks for statements that should not appear on a `DELETE` query.

Example of usage:

    delete $
    from $ \appointment ->
    where_ (appointment ^. AppointmentDate <. val now)

Unlike `select`, there is a useful way of using `delete` that will lead to type ambiguities. If you want to delete all rows (i.e., no `where_` clause), you'll have to use a type signature:

    delete $
    from $ \(appointment :: SqlExpr (Entity Appointment)) ->
    return ()

#### Database.Esqueleto.Experimental:

     delete $ do
       userFeature <- from $ table @UserFeature
       where_ ((userFeature ^. UserFeatureFeature) notIn valList allKnownFeatureFlags)

deleteCount :: (MonadIO m, SqlBackendCanWrite backend) => SqlQuery () -> ReaderT backend m Int64 Source #

Same as `delete`, but returns the number of rows affected.

update :: (MonadIO m, PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val), SqlBackendCanWrite backend) => (SqlExpr (Entity val) -> SqlQuery ()) -> ReaderT backend m () Source #

Execute an `esqueleto` `UPDATE` query inside `persistent`'s `SqlPersistT` monad. Note that currently there are no type checks for statements that should not appear on a `UPDATE` query.

Example of usage:

    update $ \p -> do
    set p [ PersonAge =. just (val thisYear) -. p ^. PersonBorn ]
    where_ $ isNothing (p ^. PersonAge)

updateCount :: (MonadIO m, PersistEntity val, BackendCompatible SqlBackend (PersistEntityBackend val), SqlBackendCanWrite backend) => (SqlExpr (Entity val) -> SqlQuery ()) -> ReaderT backend m Int64 Source #

Same as `update`, but returns the number of rows affected.

builderToText :: Builder -> Text Source #

toRawSql :: (SqlSelect a r, BackendCompatible SqlBackend backend) => Mode -> (backend, IdentState) -> SqlQuery a -> (Builder, [PersistValue]) Source #

(Internal) Pretty prints a `SqlQuery` into a SQL query.

Note: if you're curious about the SQL query being generated by `esqueleto`, instead of manually using this function (which is possible but tedious), see the `renderQueryToText` function (along with `renderQuerySelect`, `renderQueryUpdate`, etc).

renderQueryToText Source #

Arguments

:: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) |
=> Mode | Whether to render as an `SELECT`, `DELETE`, etc.
-> SqlQuery a | The SQL query you want to render.
-> ReaderT backend m (Text, [PersistValue]) |

Renders a `SqlQuery` into a `Text` value along with the list of `PersistValue`s that would be supplied to the database for `?` placeholders.

You must ensure that the `Mode` you pass to this function corresponds with the actual `SqlQuery`. If you pass a query that uses incompatible features (like an `INSERT` statement with a `SELECT` mode) then you'll get a weird result.

Since: 3.1.1

renderQuerySelect Source #

Arguments

:: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) |
=> SqlQuery a | The SQL query you want to render.
-> ReaderT backend m (Text, [PersistValue]) |

Renders a `SqlQuery` into a `Text` value along with the list of `PersistValue`s that would be supplied to the database for `?` placeholders.

Since: 3.1.1

renderQueryDelete Source #

Arguments

:: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) |
=> SqlQuery a | The SQL query you want to render.
-> ReaderT backend m (Text, [PersistValue]) |

Renders a `SqlQuery` into a `Text` value along with the list of `PersistValue`s that would be supplied to the database for `?` placeholders.

Since: 3.1.1

renderQueryUpdate Source #

Arguments

:: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) |
=> SqlQuery a | The SQL query you want to render.
-> ReaderT backend m (Text, [PersistValue]) |

Renders a `SqlQuery` into a `Text` value along with the list of `PersistValue`s that would be supplied to the database for `?` placeholders.

Since: 3.1.1

renderQueryInsertInto Source #

Arguments

:: (SqlSelect a r, BackendCompatible SqlBackend backend, Monad m) |
=> SqlQuery a | The SQL query you want to render.
-> ReaderT backend m (Text, [PersistValue]) |

Renders a `SqlQuery` into a `Text` value along with the list of `PersistValue`s that would be supplied to the database for `?` placeholders.

Since: 3.1.1

data Mode Source #

(Internal) Mode of query being converted by `toRawSql`.

Constructors

SELECT |
DELETE |
UPDATE |
INSERT_INTO |

uncommas :: [Builder] -> Builder Source #

intersperseB :: Builder -> [Builder] -> Builder Source #

uncommas' :: Monoid a => [(Builder, a)] -> (Builder, a) Source #

makeCte :: IdentInfo -> [CommonTableExpressionClause] -> (Builder, [PersistValue]) Source #

makeInsertInto :: SqlSelect a r => IdentInfo -> Mode -> a -> (Builder, [PersistValue]) Source #

makeSelect :: SqlSelect a r => IdentInfo -> Mode -> DistinctClause -> a -> (Builder, [PersistValue]) Source #

makeFrom :: IdentInfo -> Mode -> [FromClause] -> (Builder, [PersistValue]) Source #

makeSet :: IdentInfo -> [SetClause] -> (Builder, [PersistValue]) Source #

makeWhere :: IdentInfo -> WhereClause -> (Builder, [PersistValue]) Source #

makeGroupBy :: IdentInfo -> GroupByClause -> (Builder, [PersistValue]) Source #

makeHaving :: IdentInfo -> WhereClause -> (Builder, [PersistValue]) Source #

makeOrderByNoNewline :: IdentInfo -> [OrderByClause] -> (Builder, [PersistValue]) Source #

makeOrderBy :: IdentInfo -> [OrderByClause] -> (Builder, [PersistValue]) Source #

makeLimit :: IdentInfo -> LimitClause -> (Builder, [PersistValue]) Source #

makeLocking :: IdentInfo -> LockingClause -> (Builder, [PersistValue]) Source #

parens :: Builder -> Builder Source #

aliasedEntityColumnIdent :: Ident -> FieldDef -> Ident Source #

aliasedColumnName :: Ident -> IdentInfo -> Text -> Builder Source #

class SqlSelect a r | a -> r, r -> a where Source #

(Internal) Class for mapping results coming from `SqlQuery` into actual results.

This looks very similar to `RawSql`, and it is! However, there are some crucial differences and ultimately they're different classes.

Minimal complete definition

sqlSelectCols, sqlSelectColCount, sqlSelectProcessRow

Methods

sqlSelectCols :: IdentInfo -> a -> (Builder, [PersistValue]) Source #

Creates the variable part of the `SELECT` query and returns the list of `PersistValue`s that will be given to `rawQuery`.

sqlSelectColCount :: Proxy a -> Int Source #

Number of columns that will be consumed.

sqlSelectProcessRow :: [PersistValue] -> Either Text r Source #

Transform a row of the result into the data type.

sqlInsertInto :: IdentInfo -> a -> (Builder, [PersistValue]) Source #

Create `INSERT INTO` clause instead.

#### Instances

Instances details

SqlSelect () () Source # | Not useful for `select`, but used for `update` and `delete`.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> () -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy () -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text () Source # sqlInsertInto :: IdentInfo -> () -> (Builder, [PersistValue]) Source #
PersistEntity e => SqlSelect (SqlExpr (Insertion e)) (Insertion e) Source # | `INSERT INTO` hack.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Insertion e)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Insertion e) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Insertion e) -> (Builder, [PersistValue]) Source #
PersistField a => SqlSelect (SqlExpr (Value a)) (Value a) Source # | You may return any single value (i.e. a single column) from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Value a)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Value a) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source #
PersistEntity a => SqlSelect (SqlExpr (Entity a)) (Entity a) Source # | You may return an `Entity` from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> SqlExpr (Entity a) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (SqlExpr (Entity a)) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (Entity a) Source # sqlInsertInto :: IdentInfo -> SqlExpr (Entity a) -> (Builder, [PersistValue]) Source #
PersistEntity a => SqlSelect (SqlExpr (Maybe (Entity a))) (Maybe (Entity a)) Source # | You may return a possibly-`NULL` `Entity` from a `select` query.

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> SqlExpr (Maybe (Entity a)) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (SqlExpr (Maybe (Entity a))) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (Maybe (Entity a)) Source #

sqlInsertInto :: IdentInfo -> SqlExpr (Maybe (Entity a)) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb) => SqlSelect (a :& b) (ra :& rb) Source # | You may return joined values from a `select` query - this is identical to the tuple instance, but is provided for convenience. Since: 3.5.2.0
Instance details Defined in Database.Esqueleto.Experimental.From.Join Methods sqlSelectCols :: IdentInfo -> (a :& b) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a :& b) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra :& rb) Source # sqlInsertInto :: IdentInfo -> (a :& b) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb) => SqlSelect (a, b) (ra, rb) Source # | You may return tuples (up to 16-tuples) and tuples of tuples from a `select` query.
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> (a, b) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a, b) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb) Source # sqlInsertInto :: IdentInfo -> (a, b) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc) => SqlSelect (a, b, c) (ra, rb, rc) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> (a, b, c) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a, b, c) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc) Source # sqlInsertInto :: IdentInfo -> (a, b, c) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd) => SqlSelect (a, b, c, d) (ra, rb, rc, rd) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> (a, b, c, d) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a, b, c, d) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd) Source # sqlInsertInto :: IdentInfo -> (a, b, c, d) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re) => SqlSelect (a, b, c, d, e) (ra, rb, rc, rd, re) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> (a, b, c, d, e) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a, b, c, d, e) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re) Source # sqlInsertInto :: IdentInfo -> (a, b, c, d, e) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf) => SqlSelect (a, b, c, d, e, f) (ra, rb, rc, rd, re, rf) Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f) -> (Builder, [PersistValue]) Source # sqlSelectColCount :: Proxy (a, b, c, d, e, f) -> Int Source # sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf) Source # sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f) -> (Builder, [PersistValue]) Source #
(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg) => SqlSelect (a, b, c, d, e, f, g) (ra, rb, rc, rd, re, rf, rg) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh) => SqlSelect (a, b, c, d, e, f, g, h) (ra, rb, rc, rd, re, rf, rg, rh) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri) => SqlSelect (a, b, c, d, e, f, g, h, i) (ra, rb, rc, rd, re, rf, rg, rh, ri) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj) => SqlSelect (a, b, c, d, e, f, g, h, i, j) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk, SqlSelect l rl) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k, l) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk, SqlSelect l rl, SqlSelect m rm) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k, l, m) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk, SqlSelect l rl, SqlSelect m rm, SqlSelect n rn) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k, l, m, n) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk, SqlSelect l rl, SqlSelect m rm, SqlSelect n rn, SqlSelect o ro) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn, ro) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn, ro) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (Builder, [PersistValue]) Source #

(SqlSelect a ra, SqlSelect b rb, SqlSelect c rc, SqlSelect d rd, SqlSelect e re, SqlSelect f rf, SqlSelect g rg, SqlSelect h rh, SqlSelect i ri, SqlSelect j rj, SqlSelect k rk, SqlSelect l rl, SqlSelect m rm, SqlSelect n rn, SqlSelect o ro, SqlSelect p rp) => SqlSelect (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn, ro, rp) Source # |

Instance details

Defined in Database.Esqueleto.Internal.Internal

Methods

sqlSelectCols :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> (Builder, [PersistValue]) Source #

sqlSelectColCount :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> Int Source #

sqlSelectProcessRow :: [PersistValue] -> Either Text (ra, rb, rc, rd, re, rf, rg, rh, ri, rj, rk, rl, rm, rn, ro, rp) Source #

sqlInsertInto :: IdentInfo -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> (Builder, [PersistValue]) Source #

unescapedColumnNames :: EntityDef -> [DBName] Source #

getEntityVal :: Proxy (SqlExpr (Entity a)) -> Proxy a Source #

materializeExpr :: IdentInfo -> SqlExpr (Value a) -> (Builder, [PersistValue]) Source #

Materialize a `SqlExpr (Value a)`.

from3P :: Proxy (a, b, c) -> Proxy ((a, b), c) Source #

from3 :: (a, b, c) -> ((a, b), c) Source #

to3 :: ((a, b), c) -> (a, b, c) Source #

from4P :: Proxy (a, b, c, d) -> Proxy ((a, b), (c, d)) Source #

from4 :: (a, b, c, d) -> ((a, b), (c, d)) Source #

to4 :: ((a, b), (c, d)) -> (a, b, c, d) Source #

from5P :: Proxy (a, b, c, d, e) -> Proxy ((a, b), (c, d), e) Source #

from5 :: (a, b, c, d, e) -> ((a, b), (c, d), e) Source #

to5 :: ((a, b), (c, d), e) -> (a, b, c, d, e) Source #

from6P :: Proxy (a, b, c, d, e, f) -> Proxy ((a, b), (c, d), (e, f)) Source #

from6 :: (a, b, c, d, e, f) -> ((a, b), (c, d), (e, f)) Source #

to6 :: ((a, b), (c, d), (e, f)) -> (a, b, c, d, e, f) Source #

from7P :: Proxy (a, b, c, d, e, f, g) -> Proxy ((a, b), (c, d), (e, f), g) Source #

from7 :: (a, b, c, d, e, f, g) -> ((a, b), (c, d), (e, f), g) Source #

to7 :: ((a, b), (c, d), (e, f), g) -> (a, b, c, d, e, f, g) Source #

from8P :: Proxy (a, b, c, d, e, f, g, h) -> Proxy ((a, b), (c, d), (e, f), (g, h)) Source #

from8 :: (a, b, c, d, e, f, g, h) -> ((a, b), (c, d), (e, f), (g, h)) Source #

to8 :: ((a, b), (c, d), (e, f), (g, h)) -> (a, b, c, d, e, f, g, h) Source #

from9P :: Proxy (a, b, c, d, e, f, g, h, i) -> Proxy ((a, b), (c, d), (e, f), (g, h), i) Source #

from9 :: (a, b, c, d, e, f, g, h, i) -> ((a, b), (c, d), (e, f), (g, h), i) Source #

to9 :: ((a, b), (c, d), (e, f), (g, h), i) -> (a, b, c, d, e, f, g, h, i) Source #

from10P :: Proxy (a, b, c, d, e, f, g, h, i, j) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j)) Source #

from10 :: (a, b, c, d, e, f, g, h, i, j) -> ((a, b), (c, d), (e, f), (g, h), (i, j)) Source #

to10 :: ((a, b), (c, d), (e, f), (g, h), (i, j)) -> (a, b, c, d, e, f, g, h, i, j) Source #

from11P :: Proxy (a, b, c, d, e, f, g, h, i, j, k) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), k) Source #

from11 :: (a, b, c, d, e, f, g, h, i, j, k) -> ((a, b), (c, d), (e, f), (g, h), (i, j), k) Source #

to11 :: ((a, b), (c, d), (e, f), (g, h), (i, j), k) -> (a, b, c, d, e, f, g, h, i, j, k) Source #

from12P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l)) Source #

from12 :: (a, b, c, d, e, f, g, h, i, j, k, l) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l)) Source #

to12 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l)) -> (a, b, c, d, e, f, g, h, i, j, k, l) Source #

from13P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m) Source #

from13 :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m) Source #

to13 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) Source #

from14P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n)) Source #

from14 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n)) Source #

to14 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n)) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) Source #

from15P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o) Source #

from15 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o) Source #

to15 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) Source #

from16P :: Proxy (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> Proxy ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p)) Source #

from16 :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) -> ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p)) Source #

to16 :: ((a, b), (c, d), (e, f), (g, h), (i, j), (k, l), (m, n), (o, p)) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) Source #

insertSelect :: (MonadIO m, PersistEntity a, SqlBackendCanWrite backend) => SqlQuery (SqlExpr (Insertion a)) -> ReaderT backend m () Source #

Insert a `PersistField` for every selected value.

Since: 2.4.2

insertSelectCount :: (MonadIO m, PersistEntity a, SqlBackendCanWrite backend) => SqlQuery (SqlExpr (Insertion a)) -> ReaderT backend m Int64 Source #

Insert a `PersistField` for every selected value, return the count afterward

renderExpr :: SqlBackend -> SqlExpr (Value Bool) -> Text Source #

Renders an expression into `Text`. Only useful for creating a textual representation of the clauses passed to an On clause.

Since: 3.2.0

data RenderExprException Source #

An exception thrown by `RenderExpr` - it's not designed to handle composite keys, and will blow up if you give it one.

Since: 3.2.0

Constructors

RenderExprUnexpectedECompositeKey Text |

#### Instances

Instances details

Exception RenderExprException Source # | Since: 3.2.0
Instance details Defined in Database.Esqueleto.Internal.Internal Methods toException :: RenderExprException -> SomeException Source # fromException :: SomeException -> Maybe RenderExprException Source # displayException :: RenderExprException -> String Source #
Show RenderExprException Source # |
Instance details Defined in Database.Esqueleto.Internal.Internal Methods showsPrec :: Int -> RenderExprException -> ShowS Source # show :: RenderExprException -> String Source # showList :: [RenderExprException] -> ShowS Source #

valkey :: (ToBackendKey SqlBackend entity, PersistField (Key entity)) => Int64 -> SqlExpr (Value (Key entity)) Source #

`valkey i = `val` . `toSqlKey`` (https://github.com/prowdsponsor/esqueleto/issues/9).

valJ :: PersistField (Key entity) => Value (Key entity) -> SqlExpr (Value (Key entity)) Source #

`valJ` is like `val` but for something that is already a `Value`. The use case it was written for was, given a `Value` lift the `Key` for that `Value` into the query expression in a type safe way. However, the implementation is more generic than that so we call it `valJ`.

Its important to note that the input entity and the output entity are constrained to be the same by the type signature on the function (https://github.com/prowdsponsor/esqueleto/pull/69).

Since: 1.4.2

deleteKey :: (PersistStore backend, BaseBackend backend ~ PersistEntityBackend val, MonadIO m, PersistEntity val) => Key val -> ReaderT backend m () Source #

Synonym for `delete` that does not clash with `esqueleto`'s `delete`.

associateJoin :: forall e1 e0. Ord (Key e0) => [(Entity e0, e1)] -> Map (Key e0) (e0, [e1]) Source #

Avoid N+1 queries and join entities into a map structure.

This function is useful to call on the result of a single `JOIN`. For example, suppose you have this query:

    getFoosAndNestedBarsFromParent
        :: ParentId
        -> SqlPersistT IO [(Entity Foo, Maybe (Entity Bar))]
    getFoosAndNestedBarsFromParent parentId =
        select $ do
            (foo :& bar) <- from $
                table Foo
                `LeftOuterJoin`
                table Bar
                    `on` do
                        \(foo :& bar) ->
                            foo ^. FooId ==. bar ?. BarFooId
            where_ $
                foo ^. FooParentId ==. val parentId
            pure (foo, bar)

This is a natural result type for SQL - a list of tuples. However, it's not what we usually want in Haskell - each `Foo` in the list will be represented multiple times, once for each `Bar`.

We can write ``fmap` `associateJoin`` and it will translate it into a `Map` that is keyed on the `Key` of the left `Entity`, and the value is a tuple of the entity's value as well as the list of each coresponding entity.

    getFoosAndNestedBarsFromParentHaskellese
        :: ParentId
        -> SqlPersistT (Map (Key Foo) (Foo, [Maybe (Entity Bar)]))
    getFoosAndNestedBarsFromParentHaskellese parentId =
        fmap associateJoin $ getFoosdAndNestedBarsFromParent parentId

What if you have multiple joins?

Let's use `associateJoin` with a *two* join query.

    userPostComments
        :: SqlQuery (SqlExpr (Entity User, Entity Post, Entity Comment))
    userPostsComment = do
        (u :& p :& c) <- from $
            table User
            `InnerJoin`
            table Post
                on do
                    \(u :& p) ->
                        u ^. UserId ==. p ^. PostUserId
            `InnerJoin`
            table @Comment
                `on` do
                    \(_ :& p :& c) ->
                        p ^. PostId ==. c ^. CommentPostId
        pure (u, p, c)

This query returns a User, with all of the users Posts, and then all of the Comments on that post.

First, we *nest* the tuple.

    nest :: (a, b, c) -> (a, (b, c))
    nest (a, b, c) = (a, (b, c))

This makes the return of the query conform to the input expected from `associateJoin`.

    nestedUserPostComments
        :: SqlPersistT IO [(Entity User, (Entity Post, Entity Comment))]
    nestedUserPostComments =
        fmap nest $ select userPostsComments

Now, we can call `associateJoin` on it.

    associateUsers
        :: [(Entity User, (Entity Post, Entity Comment))]
        -> Map UserId (User, [(Entity Post, Entity Comment)])
    associateUsers =
        associateJoin

Next, we'll use the `Functor` instances for `Map` and tuple to call `associateJoin` on the `[(Entity Post, Entity Comment)]`.

    associatePostsAndComments
        :: Map UserId (User, [(Entity Post, Entity Comment)])
        -> Map UserId (User, Map PostId (Post, [Entity Comment]))
    associatePostsAndComments =
        fmap (fmap associateJoin)

For more reading on this topic, see this Foxhound Systems blog post.

Since: 3.1.2