Create a function creates a user-defined function. This can be written in C, PL1, Cobol, Assembler.
Create Function
CREATE FUNCTION DOCMATCH (VARCHAR(30), VARCHAR(255))
RETURNS TABLE (DOC_ID CHAR(16), DOC_ABSTRACT VARCHAR(5000))
EXTERNAL NAME 'DOCMTCH'
LANGUAGE COBOL
PARAMETER STYLE SQL
READS SQL DATA
DETERMINISTIC
NO EXTERNAL ACTION
FENCED
SCRATCHPAD
FINAL CALL
DISALLOW PARALLEL
CARDINALITY 20;