PostgreSQL 19 ← 18
← Catalog atlas / pg_foreign_data_wrapper
SYSTEM CATALOG · System catalog
pg_foreign_data_wrapper
The catalog pg_foreign_data_wrapper stores foreign-data wrapper definitions. A foreign-data wrapper is the mechanism by which external data, residing on foreign servers, is accessed.
Checked column by column against a PostgreSQL 18.6 instance · Raw measurement record ↗
Columns PostgreSQL 18
pg_foreign_data_wrapperPostgreSQL 19 beta 3 is a preview snapshot; the structure can still change before release.
| COLUMN | TYPE | DESCRIPTION |
|---|---|---|
oid |
oidNOT NULL |
Row identifier |
fdwname |
nameNOT NULL |
Name of the foreign-data wrapper |
fdwowner |
oidNOT NULL |
Owner of the foreign-data wrapperReferences:pg_authid.oid |
fdwhandler |
oidNOT NULL |
References a handler function that is responsible for supplying execution routines for the foreign-data wrapper. Zero if no handler is providedReferences:pg_proc.oid |
fdwvalidator |
oidNOT NULL |
References a validator function that is responsible for checking the validity of the options given to the foreign-data wrapper, as well as options for foreign servers and user mappings using the foreign-data wrapper. Zero if no validator is providedReferences:pg_proc.oid |
fdwacl |
aclitem[] |
Access privileges; see Section 5.8 for details |
fdwoptions |
text[] |
Foreign-data wrapper specific options, as “keyword=value” strings |
Columns marked "implicit" are not included in SELECT *; some early statistics views are completed from same-version source, and the extra provenance is shown in the column description.
Common system columns 6
System attributes PostgreSQL provides, normally not expanded by SELECT *. Kept separately so they are not mixed in with ordinary columns.
| Columns | Type | attnum |
|---|---|---|
tableoid | oid | -6 |
cmax | cid | -5 |
xmax | xid | -4 |
cmin | cid | -3 |
xmin | xid | -2 |
ctid | tid | -1 |
Column evolution matrix
Hover a cell for the column typePresentAdded / type or attribute changeRemoved
| COLUMN | 9.0 | 9.1 | 9.2 | 9.3 | 9.4 | 9.5 | 9.6 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
oid |
|||||||||||||||||
fdwname |
|||||||||||||||||
fdwowner |
|||||||||||||||||
fdwvalidator |
|||||||||||||||||
fdwacl |
|||||||||||||||||
fdwoptions |
|||||||||||||||||
fdwhandler |
– | ||||||||||||||||
fdwconnection |
– | – | – | – | – | – | – | – | – | – | – | – | – | – | – | – |
9.0 is the coverage baseline; a column already present in the baseline is not marked as added. The matrix aligns columns by name, so a rename appears as the old column removed and a new column added.
Evolution timeline
Changes between adjacent majorsPostgreSQL 17 ← 16
PostgreSQL 12 ← 11
PostgreSQL 10 ← 9.6
PostgreSQL 9.3 ← 9.2
PostgreSQL 9.1 ← 9.0
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