PG_RANGE

PG_RANGE records information about range types.

This is in addition to the types' entries in PG_TYPE.

Table 1 PG_RANGE columns

Name

Type

Reference

Description

rngtypid

oid

PG_TYPE.oid

OID of the range type

rngsubtype

oid

PG_TYPE.oid

OID of the element type (subtype) of this range type

rngcollation

oid

PG_COLLATION.oid

OID of the collation used for range comparisons, or 0 if none

rngsubopc

oid

PG_OPCLASS.oid

OID of the subtype's operator class used for range comparisons

rngsubopc (plus rngcollation, if the element type is collatable) determines the sort ordering used by the range type. rngcanonical is used when the element type is discrete.

rngcanonical

regproc

PG_PROC.oid

OID of the function to convert a range value into canonical form, or 0 if none

rngsubdiff

regproc

PG_PROC.oid

OID of the function to return the difference between two element values as double precision, or 0 if none