55.5. pg_amproc
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 55.5. pg_amproc Columns
Column Type Description |
|---|
Row identifier |
The operator family this entry is for |
Left-hand input data type of associated operator |
Right-hand input data type of associated operator |
Support function number |
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.