Presto 0.244 Documentation

10.1. ALTER FUNCTION

10.1. ALTER FUNCTION

Synopsis

ALTER FUNCTION qualified_function_name [ ( parameter_type[, ...] ) ]
RETURNS NULL ON NULL INPUT | CALLED ON NULL INPUT

Description

Alter the definition of an existing function.

Parameter type list must be specified if multiple signatures exist for the specified function name. If exactly one signature exists for the specified function name, parameter type list can be omitted.

Currently, only modifying the null-call clause is supported.

Examples

Change the null-call clause of a function example.default.tan(double):

ALTER FUNCTION prod.default.tan(double)
CALLED ON NULL INPUT

If only one function exists for example.default.tan, parameter type list may be omitted:

ALTER FUNCTION prod.default.tan
CALLED ON NULL INPUT