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 PROCEDUREEXTERNAL FUNCTION 

CREATE OR ALTER FUNCTION

Creates a stored function if it does not exist, or alters a stored function

Available in

DSQL

Syntax
CREATE OR ALTER FUNCTION funcname
  [ ( [ <in_params> ] ) ]
  RETURNS <domain_or_non_array_type> [COLLATE collation]
  [DETERMINISTIC]
  {<psql_function> | <external-module-body>}

!! See syntax of CREATE FUNCTION for further rules !!

The CREATE OR ALTER FUNCTION statement creates a new stored function or alters an existing one.If the stored function does not exist, it will be created by invoking a CREATE FUNCTION statement transparently.If the function already exists, it will be altered and compiled (through ALTER FUNCTION) without affecting its existing privileges and dependencies.

Examples of CREATE OR ALTER FUNCTION

Create a new or alter an existing stored function
CREATE OR ALTER FUNCTION ADD_INT(A INT, B INT DEFAULT 0)
RETURNS INT
AS
BEGIN
  RETURN A + B;
END

DROP FUNCTION

Drops a stored function

Available in

DSQL

Syntax
DROP FUNCTION funcname
Table 1. DROP FUNCTION Statement Parameters
Parameter Description

funcname

Stored function name.The maximum length is 63 characters.Must be unique among all function names in the database.

The DROP FUNCTION statement deletes an existing stored function.If the stored function has any dependencies, the attempt to delete it will fail, and raise an error.

Who Can Drop a Function

The DROP FUNCTION statement can be executed by:

  • Administrators

  • Owner of the stored function

  • Users with the DROP ANY FUNCTION privilege

RECREATE FUNCTION

Drops a stored function if it exists, and creates a stored function

Available in

DSQL

Syntax
RECREATE FUNCTION funcname
  [ ( [ <in_params> ] ) ]
  RETURNS <domain_or_non_array_type> [COLLATE collation]
  [DETERMINISTIC]
  {<psql_function> | <external-module-body>}

!! See syntax of CREATE FUNCTION for further rules !!

The RECREATE FUNCTION statement creates a new stored function or recreates an existing one.If there is a function with this name already, the engine will try to drop it and then create a new one.Recreating an existing function will fail at COMMIT if the function has dependencies.

Note

Be aware that dependency errors are not detected until the COMMIT phase of this operation.

After a procedure is successfully recreated, existing privileges to execute the stored function and theprivileges of the stored function itself are dropped.

Examples of RECREATE FUNCTION

Creating or recreating a stored function
RECREATE FUNCTION ADD_INT(A INT, B INT DEFAULT 0)
RETURNS INT
AS
BEGIN
  RETURN A + B;
EN