drop_operator_class(7) [centos man page]
DROP OPERATOR
CLASS(7) PostgreSQL 9.2.7 Documentation DROP OPERATOR CLASS(7) NAME
DROP_OPERATOR_CLASS - remove an operator class SYNOPSIS
DROP OPERATOR CLASS [ IF EXISTS ] name USING index_method [ CASCADE | RESTRICT ] DESCRIPTION
DROP OPERATOR CLASS drops an existing operator class. To execute this command you must be the owner of the operator class. DROP OPERATOR CLASS does not drop any of the operators or functions referenced by the class. If there are any indexes depending on the operator class, you will need to specify CASCADE for the drop to complete. PARAMETERS
IF EXISTS Do not throw an error if the operator class does not exist. A notice is issued in this case. name The name (optionally schema-qualified) of an existing operator class. index_method The name of the index access method the operator class is for. CASCADE Automatically drop objects that depend on the operator class. RESTRICT Refuse to drop the operator class if any objects depend on it. This is the default. NOTES
DROP OPERATOR CLASS will not drop the operator family containing the class, even if there is nothing else left in the family (in particular, in the case where the family was implicitly created by CREATE OPERATOR CLASS). An empty operator family is harmless, but for the sake of tidiness you might wish to remove the family with DROP OPERATOR FAMILY; or perhaps better, use DROP OPERATOR FAMILY in the first place. EXAMPLES
Remove the B-tree operator class widget_ops: DROP OPERATOR CLASS widget_ops USING btree; This command will not succeed if there are any existing indexes that use the operator class. Add CASCADE to drop such indexes along with the operator class. COMPATIBILITY
There is no DROP OPERATOR CLASS statement in the SQL standard. SEE ALSO
ALTER OPERATOR CLASS (ALTER_OPERATOR_CLASS(7)), CREATE OPERATOR CLASS (CREATE_OPERATOR_CLASS(7)), DROP OPERATOR FAMILY (DROP_OPERATOR_FAMILY(7)) PostgreSQL 9.2.7 2014-02-17 DROP OPERATOR CLASS(7)
Check Out this Related Man Page
ALTER OPERATOR
FAMILY(7) SQL Commands ALTER OPERATOR FAMILY(7) NAME
ALTER OPERATOR FAMILY - change the definition of an operator family SYNOPSIS
ALTER OPERATOR FAMILY name USING index_method ADD { OPERATOR strategy_number operator_name ( op_type, op_type ) | FUNCTION support_number [ ( op_type [ , op_type ] ) ] funcname ( argument_type [, ...] ) } [, ... ] ALTER OPERATOR FAMILY name USING index_method DROP { OPERATOR strategy_number ( op_type [ , op_type ] ) | FUNCTION support_number ( op_type [ , op_type ] ) } [, ... ] ALTER OPERATOR FAMILY name USING index_method RENAME TO newname ALTER OPERATOR FAMILY name USING index_method OWNER TO newowner DESCRIPTION
ALTER OPERATOR FAMILY changes the definition of an operator family. You can add operators and support functions to the family, remove them from the family, or change the family's name or owner. When operators and support functions are added to a family with ALTER OPERATOR FAMILY, they are not part of any specific operator class within the family, but are just ``loose'' within the family. This indicates that these operators and functions are compatible with the fam- ily's semantics, but are not required for correct functioning of any specific index. (Operators and functions that are so required should be declared as part of an operator class, instead; see CREATE OPERATOR CLASS [create_operator_class(7)].) PostgreSQL will allow loose mem- bers of a family to be dropped from the family at any time, but members of an operator class cannot be dropped without dropping the whole class and any indexes that depend on it. Typically, single-data-type operators and functions are part of operator classes because they are needed to support an index on that specific data type, while cross-data-type operators and functions are made loose members of the family. You must be a superuser to use ALTER OPERATOR FAMILY. (This restriction is made because an erroneous operator family definition could con- fuse or even crash the server.) ALTER OPERATOR FAMILY does not presently check whether the operator family definition includes all the operators and functions required by the index method, nor whether the operators and functions form a self-consistent set. It is the user's responsibility to define a valid operator family. Refer to in the documentation for further information. PARAMETERS
name The name (optionally schema-qualified) of an existing operator family. index_method The name of the index method this operator family is for. strategy_number The index method's strategy number for an operator associated with the operator family. operator_name The name (optionally schema-qualified) of an operator associated with the operator family. op_type In an OPERATOR clause, the operand data type(s) of the operator, or NONE to signify a left-unary or right-unary operator. Unlike the comparable syntax in CREATE OPERATOR CLASS, the operand data types must always be specified. In an ADD FUNCTION clause, the operand data type(s) the function is intended to support, if different from the input data type(s) of the function. For B-tree and hash indexes it is not necessary to specify op_type since the function's input data type(s) are always the correct ones to use. For GIN and GiST indexes it is necessary to specify the input data type the function is to be used with. In a DROP FUNCTION clause, the operand data type(s) the function is intended to support must be specified. support_number The index method's support procedure number for a function associated with the operator family. funcname The name (optionally schema-qualified) of a function that is an index method support procedure for the operator family. argument_types The parameter data type(s) of the function. newname The new name of the operator family. newowner The new owner of the operator family. The OPERATOR and FUNCTION clauses can appear in any order. NOTES
Notice that the DROP syntax only specifies the ``slot'' in the operator family, by strategy or support number and input data type(s). The name of the operator or function occupying the slot is not mentioned. Also, for DROP FUNCTION the type(s) to specify are the input data type(s) the function is intended to support; for GIN and GiST indexes this might have nothing to do with the actual input argument types of the function. Because the index machinery does not check access permissions on functions before using them, including a function or operator in an opera- tor family is tantamount to granting public execute permission on it. This is usually not an issue for the sorts of functions that are use- ful in an operator family. The operators should not be defined by SQL functions. A SQL function is likely to be inlined into the calling query, which will prevent the optimizer from recognizing that the query matches an index. Before PostgreSQL 8.4, the OPERATOR clause could include a RECHECK option. This is no longer supported because whether an index operator is ``lossy'' is now determined on-the-fly at runtime. This allows efficient handling of cases where an operator might or might not be lossy. EXAMPLES
The following example command adds cross-data-type operators and support functions to an operator family that already contains B-tree oper- ator classes for data types int4 and int2. ALTER OPERATOR FAMILY integer_ops USING btree ADD -- int4 vs int2 OPERATOR 1 < (int4, int2) , OPERATOR 2 <= (int4, int2) , OPERATOR 3 = (int4, int2) , OPERATOR 4 >= (int4, int2) , OPERATOR 5 > (int4, int2) , FUNCTION 1 btint42cmp(int4, int2) , -- int2 vs int4 OPERATOR 1 < (int2, int4) , OPERATOR 2 <= (int2, int4) , OPERATOR 3 = (int2, int4) , OPERATOR 4 >= (int2, int4) , OPERATOR 5 > (int2, int4) , FUNCTION 1 btint24cmp(int2, int4) ; To remove these entries again: ALTER OPERATOR FAMILY integer_ops USING btree DROP -- int4 vs int2 OPERATOR 1 (int4, int2) , OPERATOR 2 (int4, int2) , OPERATOR 3 (int4, int2) , OPERATOR 4 (int4, int2) , OPERATOR 5 (int4, int2) , FUNCTION 1 (int4, int2) , -- int2 vs int4 OPERATOR 1 (int2, int4) , OPERATOR 2 (int2, int4) , OPERATOR 3 (int2, int4) , OPERATOR 4 (int2, int4) , OPERATOR 5 (int2, int4) , FUNCTION 1 (int2, int4) ; COMPATIBILITY
There is no ALTER OPERATOR FAMILY statement in the SQL standard. SEE ALSO
CREATE OPERATOR FAMILY [create_operator_family(7)], DROP OPERATOR FAMILY [drop_operator_family(7)], CREATE OPERATOR CLASS [create_opera- tor_class(7)], ALTER OPERATOR CLASS [alter_operator_class(7)], DROP OPERATOR CLASS [drop_operator_class(7)] SQL - Language Statements 2010-05-14 ALTER OPERATOR FAMILY(7)