Stored Procedure with a IN statement (mysql)

Question

I have a query like

Select id,name,... FROM table WHERE id IN (?)

The query is actually more complicated with joins and another (?) with the same ids. I've been told to put it on a stored procedure to make it easier to manage and safer, but mysql doesn't support arrays, so I'm not sure what is the best way to do it, considering that I don't know how many id I will have to pass. I have seen people passing a string. Is it the only way?

Answer 1

You can use temporary tables. Though this answer is not highly voted so I suppose that using a string parameter is the prefered way (17 votes vs 2 votes) (see the link). The answer with temporary table is taken from another question: Pass array to MySQL stored routine

Use a join with a temporary table. You don't need to pass temporary tables to functions, they are global.

create temporary table ids( id int ) ;
insert into ids values (1),(2),(3) ;

delimiter //
drop procedure if exists tsel //
create procedure tsel() -- uses temporary table named ids. no params
READS SQL DATA
BEGIN
  -- use the temporary table `ids` in the SELECT statement or
  -- whatever query you have
  select * from Users INNER JOIN ids on userId=ids.id ;
END //
DELIMITER ;

CALL tsel() ; -- call the procedure