Question

I use db2 9.7.6 full edition for windows. I need develop functions which can be use on sql select expression.
Functions must contain modifying sql data and handling runtime exceptions. There are two variants, but I have problems of implementations all requirments in ever variants.
The first variant is implementation of sql table function, e.g.

 CREATE FUNCTION func1 (val CHAR(20))
    RETURNS table(result varchar(1000))
    LANGUAGE SQL
    MODIFIES SQL DATA
   BEGIN atomic
    insert into a values(val);
        return (select result from a);
    END 

It works, but I can’t implement handling exception how in sql procedures. When I tried to use block “declare exit handler”, I got a syntax errors.
The second variant is implementation of pl/sql function, e.g.

CREATE OR REPLACE FUNCTION bb
RETURN varchar2
MODIFIES SQL DATA
AS
BEGIN
    insert into st values ('a');
    return 0;
END bb;

But when I tried to execute this function, I got error “SQLCODE=-740, SQLSTATE=51034 is defined with the MODIFIES SQL DATA option, which is not valid in the context where the routine is invoked”. Help me please.
best regards, Turkin Andrew.

Answer 1

It just doesn’t work.

List of maximum access levels

Routine type    Default SQL access level    Maximum allowed SQL access level
SQL procedures  MODIFIES SQL DATA   MODIFIES SQL DATA
SQL functions (scalar functions)    READS SQL DATA  READS SQL DATA
SQL functions (table functions)     READS SQL DATA  MODIFIES SQL DATA
External procedures     MODIFIES SQL DATA   MODIFIES SQL DATA
External functions (scalar functions)   READS SQL DATA  READS SQL DATA
External functions (table functions)    READS SQL DATA  READS SQL DATA

For scalar functions the maximum level is “READS SQL DATA”. There is probably now way around that, so you have to reconsider your coding.