DROP FUNCTION(7) PostgreSQL 10.1 Documentation DROP FUNCTION(7)NAMEDROP_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. If
no argument list is specified, the name must be unique in its
schema.
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), and in turn all objects that depend on
those objects (see Section 5.13).
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);
Drop multiple functions in one command:
DROP FUNCTION sqrt(integer), sqrt(bigint);
If the function name is unique in its schema, it can be referred to
without an argument list:
DROP FUNCTION update_employee_salaries;
Note that this is different from
DROP FUNCTION update_employee_salaries();
which refers to a function with zero arguments, whereas the first
variant can refer to a function with any number of arguments, including
zero, as long as the name is unique.
COMPATIBILITY
This command conforms to the SQL standard, with these PostgreSQL
extensions:
· The standard only allows one function to be dropped per command.
· The IF EXISTS option
· The ability to specify argument modes and names
SEE ALSO
CREATE FUNCTION (CREATE_FUNCTION(7)), ALTER FUNCTION
(ALTER_FUNCTION(7))
PostgreSQL 10.1 2017 DROP FUNCTION(7)
