The pg_amop table stores information about operators associated with index access method operator classes. There is one row for each operator that is a member of an operator class.

    An entry’s amopmethod must match the opfmethod of its containing operator family (including amopmethod here is an intentional denormalization of the catalog structure for performance reasons). Also, amoplefttype and amoprighttype must match the oprleft and oprright fields of the referenced pg_operator entry.

    columntypereferencesdescription
    oidoid Row identifier (hidden attribute; must be explicitly selected)
    amopfamilyoidpg_opfamily.oidThe operator family that this entry is for
    amoplefttypeoidpg_type.oidLeft-hand input data type of operator
    amoprighttypeoidpg_type.oidRight-hand input data type of operator
    amopstrategyint2 Operator strategy number
    amoppurposechar Operator purpose, either s for search or o for ordering
    amopoproidpg_operator.oidOID of the operator
    amopmethodoidpg_am.oidIndex access method for the operator family
    amopsortfamilyoidpg_opfamily.oidIf an ordering operator, the B-tree operator family that this entry sorts according to; zero if a search operator

    Parent topic: System Catalogs Definitions