PGCOPYDB(5)

NAME
pgcopydb - pgcopydb

Manual page for the configuration of pgcopydb. The pgcopydb command accepts sub-commands and command line options, see the manual for those commands for details. The only setup that pgcopydb commands accept is the filtering.

FILTERING

Filtering allows to skip some object definitions and data when copying from the source to the target database. The pgcopydb commands that accept the option --filter (or --filters) expect an existing filename as the option argument. The given filename is read in the INI file format, but only uses sections and option keys. Option values are not used.

Here is an inclusion based filter configuration example:

            [include-only-schema]
            public
            ~/^audit_/

            [include-only-table]
            public.allcols
            public.csv
            public.serial
            public.xzero

            [exclude-index]
            public.foo_gin_tsvector

            [exclude-table-data]
            public.csv

Here is an exclusion based filter configuration example:

            [exclude-schema]
            foo
            bar
            expected

            [exclude-table]
            "schema"."name"
            schema.othername
            err.errors
            public.~/^tmp_/

            [exclude-index]
            schema.indexname

            [exclude-table-data]
            public.bar
            nsitra.test1

            [exclude-extension]
            aiven_extras

  Pattern matching

In any filter section that accepts schema-qualified names, each name component (schema or table) may be written as a regular-expression pattern using the syntax ~/pattern/ instead of a literal name. The ~/ prefix and trailing / are the delimiters; everything between them is a POSIX extended regular expression matched with regcomp(3) / regexec(3).

Patterns may appear as the schema part, the name part, or both:

            [exclude-table]
            ; exact schema, regex table — excludes all tables starting with "tmp_" in public
            public.~/^tmp_/

            ; regex schema, exact table — excludes "audit_log" in any schema starting with "log"
            ~/^log/.audit_log

            ; regex schema, regex table — excludes any table ending with "_bak" in any "archive" schema
            ~/archive/.~/_bak$/

For [exclude-schema] and [include-only-schema] entries are bare schema names and the whole entry is treated as the pattern:

            [exclude-schema]
            ; excludes every schema whose name starts with "tmp_"
            ~/^tmp_/

            [include-only-schema]
            public
            ; also include every schema whose name matches "audit_YYYY" (four digits)
            ~/^audit_[0-9]{4}$/

A pattern is matched against each object name from the source database catalog. Entries that resolve to zero matching objects are silently ignored; pgcopydb does not treat an unmatched pattern as an error.

Filtering can be done with pgcopydb by using the following rules, which are also the name of the sections of the INI file.

  include-only-table

This section allows listing the exclusive list of the source tables to copy to the target database. No other table will be processed by pgcopydb.

Each line in that section should be a schema-qualified table name. Postgres identifier quoting rules <https://www.postgresql.org/docs/current/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS> can be used to avoid ambiguity. Either the schema component or the table component (or both) may be a ~/pattern/ regex instead of a literal name; see Pattern matching above.

When the section include-only-table is used in the filtering configuration then the sections exclude-schema and exclude-table are disallowed. We would not know how to handle tables that exist on the source database and are not part of any filter.

NOTE: Materialized views are also considered as tables during the filtering.

  exclude-schema

This section allows adding schemas (Postgres namespaces) to the exclusion filters. All the tables that belong to any listed schema in this section are going to be ignored by the pgcopydb command.

Each line is a bare schema name or a ~/pattern/ regex that is matched against schema names; see Pattern matching above.

This section is not allowed when the section include-only-table is used.

  include-only-schema

This section restricts processing to the listed schemas: only tables that belong to one of the named schemas are copied; all others are skipped. This is a syntactic shortcut for excluding every other schema without having to list them all under exclude-schema.

Despite the name, this section is implemented as an exclusion filter.

Each line is a bare schema name or a ~/pattern/ regex that is matched against schema names; see Pattern matching above.

This section is not allowed when the section exclude-schema is used.

  exclude-table

This section allows to add a list of qualified table names to the exclusion filters. All the tables that are listed in the exclude-table section are going to be ignored by the pgcopydb command.

Each line is a schema-qualified table name. Either the schema component or the table component (or both) may be a ~/pattern/ regex; see Pattern matching above.

This section is not allowed when the section include-only-table is used.

NOTE: Materialized views are also considered as tables during the filtering.

  exclude-index

This section allows to add a list of qualified index names to the exclusion filters. It is then possible for pgcopydb to operate on a table and skip a single index definition that belong to a table that is still processed.

Each line is a schema-qualified index name. Either the schema component or the index-name component (or both) may be a ~/pattern/ regex; see Pattern matching below.

  exclude-table-data

This section allows to skip copying the data from a list of qualified table names. The schema, index, constraints, etc of the table are still copied over.

Each line is a schema-qualified table name. Either the schema component or the table component (or both) may be a ~/pattern/ regex; see Pattern matching above.

NOTE: Materialized views are also considered as tables during the filtering.

  exclude-extension

This section allows to skip specific PostgreSQL extensions by name. The listed extensions are not created on the target database and their configuration tables are not copied.

Each entry is a bare extension name (no schema prefix), one per line:

            [exclude-extension]
            aiven_extras
            timescaledb

This section is not allowed when the section include-only-extension is used at the same time.

  include-only-extension

This section restricts extension handling to only the listed extensions. All other extensions found in the source database are skipped — they are not created on the target and their configuration tables are not copied.

Each entry is a bare extension name (no schema prefix), one per line:

            [include-only-extension]
            postgis
            uuid-ossp

This section is not allowed when the section exclude-extension is used at the same time, and it cannot be combined with --skip-extensions (which skips all extensions).

REVIEWING AND DEBUGGING THE FILTERS

Filtering a pg_restore archive file is done through rewriting the archive catalog obtained with pg_restore --list. That's a little hackish at times, and we also have to deal with dependencies in pgcopydb itself.

The following commands can be used to explore a set of filtering rules:

            •   pgcopydb list depends <#pgcopydb-list-depends>

            •   pgcopydb restore parse-list <#pgcopydb-restore-parse-list>

Author
Dimitri Fontaine

Copyright
2022-2024, Dimitri Fontaine