NAME

       DROP_FUNCTION - remove a function

SYNOPSIS

       DROP FUNCTION [ IF EXISTS ] name ( [ [ argmode ] [ argname ] argtype [, ...] ] )
           [ CASCADE | RESTRICT ]

DESCRIPTION

       DROP FUNCTION removes the definition of an existing function. To execute this command the
       user must be the owner of the function. The argument types to the function must be
       specified, since several different functions can exist with the same name and different
       argument lists.

PARAMETERS

       IF EXISTS
           Do not throw an error if the function does not exist. A notice is issued in this case.

       name
           The name (optionally schema-qualified) of an existing function.

       argmode
           The mode of an argument: IN, OUT, INOUT, or VARIADIC. If omitted, the default is IN.
           Note that DROP FUNCTION does not actually pay any attention to OUT arguments, since
           only the input arguments are needed to determine the function's identity. So it is
           sufficient to list the IN, INOUT, and VARIADIC arguments.

       argname
           The name of an argument. Note that DROP FUNCTION does not actually pay any attention
           to argument names, since only the argument data types are needed to determine the
           function's identity.

       argtype
           The data type(s) of the function's arguments (optionally schema-qualified), if any.

       CASCADE
           Automatically drop objects that depend on the function (such as operators or
           triggers).

       RESTRICT
           Refuse to drop the function if any objects depend on it. This is the default.

EXAMPLES

       This command removes the square root function:

           DROP FUNCTION sqrt(integer);

COMPATIBILITY

       A DROP FUNCTION statement is defined in the SQL standard, but it is not compatible with
       this command.

SEE ALSO

       CREATE FUNCTION (CREATE_FUNCTION(7)), ALTER FUNCTION (ALTER_FUNCTION(7))