PG_AMPROC¶
PG_AMPROC records information about the support procedures associated with the access method operator families. There is one row for each support procedure belonging to an operator family.
Name | Type | Reference | Description |
---|---|---|---|
oid | oid |
| Row identifier (hidden attribute; must be explicitly selected) |
amprocfamily | oid | PG_OPFAMILY.oid | Operator family this entry is for |
amproclefttype | oid | PG_TYPE.oid | Left-hand input data type of associated operator |
amprocrighttype | oid | PG_TYPE.oid | Right-hand input data type of associated operator |
amprocnum | smallint |
| Support procedure number |
amproc | regproc | PG_PROC.oid | OID of the procedure |
The usual interpretation of the amproclefttype and amprocrighttype columns is that they identify the left and right input types of the operator(s) that a particular support procedure supports. For some access methods these match the input data type(s) of the support procedure itself, for others not. There is a notion of "default" support procedures for an index, which are those with amproclefttype and amprocrighttype both equal to the index opclass's opcintype.