Hi, Say that I have a family of simple scalar transforming function f(x ,p) => y parameterized by p which are implemented as C UDF's and exposed as SQL UDF's. Is it possible to create a bulk version of this? So the scalar C signature is simplified to something like char* f(int* output, int* input, const char** func_parameter); the mal stuff module m; command f(input:int, func_parameter:str):int address f; and in sql we have CREATE FUNCTION f(input INT, func_param STRING) RETURNS INT EXTERNAL NAME m.f; Now for the bulk version I would like to use in C: char* f(bat* output, bat* input, const char** func_parameter); in MAL: module batm; command f(input:bat[:int], func_parameter:str):bat[:int] address f; in SQL: reuse the scalar SQL signature. But that doesn't seem to work. When I compile this and call the udf in a sql query on an actual column, the plan applies the scalar version on each tuple instead of calling the bulk version once. However if I remove the parametrization, i.e. removing the func_parameter from the signature, the bulk version is correctly called. Aris