MYSQL Concat() syntax error?

Question

I want to add concatenated value to the params variable in mysql procedure. But mysql says it has a syntax error. What is the syntax error I'm doing here?

SET parms =CONCAT('s','sa');

DECLARE CONTINUE HANDLER FOR NOT FOUND SET exit_loop = TRUE;

Mysql complains that the error is in 2nd line. But I think I'm doing something wrong in 1st line.

Answer 1

Your problem is that you put DECLARE in the wrong place.

DECLARE Syntax
DECLARE is permitted only inside a BEGIN ... END compound statement and must be at its start, before any other statements .

More over the declarations must follow a specific order:

1. variables and conditions
2. cursors
3. handlers

That being said, this will do just fine

DECLARE parms VARCHAR(32);
DECLARE exit_loop INT;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET exit_loop = TRUE;

SET parms = CONCAT('s','sa');

Let's try it:

mysql> DELIMITER //
mysql> CREATE PROCEDURE myproc()
    -> BEGIN
    ->   DECLARE parms VARCHAR(32);
    ->   DECLARE exit_loop INT;
    ->   DECLARE CONTINUE HANDLER FOR NOT FOUND SET exit_loop = TRUE;
    -> 
    ->   SET parms = CONCAT('s','sa');
    ->   SELECT parms;
    -> END
    -> //
Query OK, 0 rows affected (0.00 sec)

mysql> DELIMITER ;
mysql> CALL myproc();
+-------+
| parms |
+-------+
| ssa   |
+-------+
1 row in set (0.00 sec)

Query OK, 0 rows affected (0.00 sec)