Postgresql 中文操作指南

53.34. pg_operator #

目录 pg_operator 中存储了有关算符的信息。有关更多信息，请参见 CREATE OPERATOR 和 Section 38.14 。

The catalog pg_operator stores information about operators. See CREATE OPERATOR and Section 38.14 for more information.

Table 53.34. pg_operator Columns

Column Type

Description

oid oid

Row identifier

oprname name

Name of the operator

oprnamespace oid (references pg_namespace.oid)

The OID of the namespace that contains this operator

oprowner oid (references pg_authid.oid)

Owner of the operator

oprkind char

b = infix operator (“both”), or l = prefix operator (“left”)

oprcanmerge bool

This operator supports merge joins

oprcanhash bool

This operator supports hash joins

oprleft oid (references pg_type.oid)

Type of the left operand (zero for a prefix operator)

oprright oid (references pg_type.oid)

Type of the right operand

oprresult oid (references pg_type.oid)

Type of the result (zero for a not-yet-defined “shell” operator)

oprcom oid (references pg_operator.oid)

Commutator of this operator (zero if none)

oprnegate oid (references pg_operator.oid)

Negator of this operator (zero if none)

oprcode regproc (references pg_proc.oid)

Function that implements this operator (zero for a not-yet-defined “shell” operator)

oprrest regproc (references pg_proc.oid)

Restriction selectivity estimation function for this operator (zero if none)

oprjoin regproc (references pg_proc.oid)

Join selectivity estimation function for this operator (zero if none)