[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'SQLDB' (#fcl)

# TSQLSequence

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

Support for applying sequences to fields

## Declaration

Source position: sqldb.pp line 449

`type TSQLSequence = class(TPersistent)`
`public`
`constructor Create();` |  | Create a new instance
`procedure Assign(); override;` |  | Assign one TSQLSequence to another
`procedure Apply;` |  | Apply a new value to a field
`function GetNextValue;` |  | Get a next value for the sequence
`published`
`property FieldName: string; [rw]` |  | Field to apply sequence to
`property SequenceName: string; [rw]` |  | Sequence name to get values from
`property IncrementBy: Integer; [rw]` |  | Value to increment sequence with
`property ApplyEvent: TSQLSequenceApplyEvent; [rw]` |  | When to apply the new value
`end;`

## Inheritance

`TSQLSequence` |  | Support for applying sequences to fields
`TPersistent,IFPObserved`
`TObject`

## Description

TSQLSequence is an auxiliary class, used to auto-generate numerical values for fields in databases that support sequences; it is used as a property of TSQLQuery and its properties determine which field must be auto-generated, and at what moment this value must be generated.

## See also

TSQLConnection.GetSequenceNames |  | Return a list of sequence names
TSQLConnection.GetNextValue |  | Get next value for a sequence