Updated on 2023-10-23 GMT+08:00

PG_OPERATOR

PG_OPERATOR records information about operators.

Table 1 PG_OPERATOR columns

Name

Type

Reference

Description

oid

oid

-

Row identifier (hidden attribute, which must be specified)

oprname

name

-

Name of an operator

oprnamespace

oid

OID in PG_NAMESPACE

OID of the namespace that contains the operator

oprowner

oid

OID in PG_AUTHID

Owner of the operator

oprkind

"char"

-

  • b: infix ("both")
  • l: prefix ("left")
  • r: postfix ("right")

oprcanmerge

boolean

-

Whether the operator supports merge joins

  • t (true): yes
  • f (false): no

oprcanhash

boolean

-

Whether the operator supports hash joins

  • t (true): yes
  • f (false): no

oprleft

oid

OID in PG_TYPE

Type of the left operand

oprright

oid

OID in PG_TYPE

Type of the right operand

oprresult

oid

OID in PG_TYPE

Type of the result

oprcom

oid

OID in PG_OPERATOR

Commutator of this operator, if any

oprnegate

oid

OID in PG_OPERATOR

Negator of this operator, if any

oprcode

regproc

proname in PG_PROC

Function that implements the operator

oprrest

regproc

proname in PG_PROC

Restriction selectivity estimation function for the operator

oprjoin

regproc

proname in PG_PROC

Join selectivity estimation function for the operator