MySQL foreach alternative for procedure

Question

My problem is fairly simple. I have table sets that store product sets (more products looking like one on the outside - computer, mouse and keyboard for ex.) it's connected M:N using sets_products table to products table. Each product can have parameters (connected again M:N).

I have a procedure, that generates all parameters as string (for search cache - like 'hdd:120GB, LCD:1440:900, ..'), but now I need to loop through the set's products and call the procedure for each of them. I CAN'T DO IT IN PHP, because this is used in trigger.

I'd like to use something like this (pseudo SQL)

FOREACH(SELECT products_id FROM sets_products WHERE set_id = 1)     generate_parameter_list(product_id,@result)     @param = CONCAT(@param,",",@result); END FOREACH; 

Can this be done in MySQL or not?

Answer 1

Here's the mysql reference for cursors. So I'm guessing it's something like this:

  DECLARE done INT DEFAULT 0;   DECLARE products_id INT;   DECLARE result varchar(4000);   DECLARE cur1 CURSOR FOR SELECT products_id FROM sets_products WHERE set_id = 1;   DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;    OPEN cur1;    REPEAT     FETCH cur1 INTO products_id;     IF NOT done THEN       CALL generate_parameter_list(@product_id, @result);       SET param = param + "," + result; -- not sure on this syntax     END IF;   UNTIL done END REPEAT;    CLOSE cur1;    -- now trim off the trailing , if desired