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Lu, Huayi a24ca60074 DWS DEVELOPER 811 version
Reviewed-by: Hasko, Vladimir <vladimir.hasko@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
2023-01-19 13:37:49 +00:00

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PG_OPFAMILY

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.

Table 1 PG_OPFAMILY columns

Name

Type

Reference

Description

oid

oid

-

Row identifier (hidden attribute; must be explicitly selected)

opfmethod

oid

PG_AM.oid

Index access method the operator family is for

opfname

name

-

Name of the operator family

opfnamespace

oid

PG_NAMESPACE.oid

Namespace of the operator family

opfowner

oid

PG_AUTHID.oid

Owner of the operator family

The majority of the information defining an operator family is not in PG_OPFAMILY, but in the associated PG_AMOP, PG_AMPROC, and PG_OPCLASS.