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 52.5. \1 字段列说明
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.