PostgreSQL 9.6.5 Documentation | |||
---|---|---|---|
Prev | Up | Chapter 50. System Catalogs | Next |
The catalog pg_opfamily defines operator families. Each operator family is a collection of operators and associated support routines that implement the semantics specified for a particular index access method. Furthermore, the operators in a family are all "compatible", in a way that is specified by the access method. The operator family concept allows cross-data-type operators to be used with indexes and to be reasoned about using knowledge of access method semantics.
Operator families are described at length in Section 36.14.
Table 50-35. pg_opfamily Columns
Name | Type | References | Description |
---|---|---|---|
oid | oid | Row identifier (hidden attribute; must be explicitly selected) | |
opfmethod | oid | pg_am.oid | Index access method operator family is for |
opfname | name | Name of this operator family | |
opfnamespace | oid | pg_namespace.oid | Namespace of this operator family |
opfowner | oid | pg_authid.oid | Owner of the operator family |
The majority of the information defining an operator family is not in its pg_opfamily row, but in the associated rows in pg_amop, pg_amproc, and pg_opclass.