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)]