52.5. pg_amproc

52.5. `pg_amproc`
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The catalog pg_amproc stores information about support functions associated with access method operator families. There is one row for each support function belonging to an operator family.

Table 52.5. pg_amproc Columns

Name	Type	References	Description
`oid`	`oid`		Row identifier (hidden attribute; must be explicitly selected)
`amprocfamily`	`oid`	`pg_opfamily .oid`	The 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`	`int2`		Support function number
`amproc`	`regproc`	`pg_proc .oid`	OID of the function

The usual interpretation of the amproclefttype and amprocrighttype fields is that they identify the left and right input types of the operator(s) that a particular support function supports. For some access methods these match the input data type(s) of the support function itself, for others not. There is a notion of " default " support functions for an index, which are those with amproclefttype and amprocrighttype both equal to the index operator class's opcintype .

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52.4. `pg_amop`	Home	52.6. `pg_attrdef`