Question

Everytime call this stored procedure i get this error:

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'NULL' at line 1

What seems to be the problem?

Here is the code:

DELIMITER $$

DROP PROCEDURE IF EXISTS `singledb`.`TOUR_TRANSFER`$$

CREATE DEFINER=`root`@`localhost` PROCEDURE `TOUR_TRANSFER`()
BEGIN

BEGIN -- for rubric table
            DECLARE tblRubric_rubric_id INT;
            SET @qry = concat('SELECT count(*) into ',tblRubric_rubric_id,' FROM zerodb2.tour_template');
            PREPARE statement FROM @qry;
            EXECUTE statement;

            SELECT tblRubric_rubric_id;
END;
END$$

DELIMITER ;

Answer 1

From http://bugs.mysql.com/bug.php?id=15263:

"Parameter markers can be used only where data values should appear,
not for SQL keywords, identifiers, and so forth."

So, we can not do:

PREPARE stmt FROM 'SELECT id INTO ? FROM t1';

We can not use ? instead of identifier (variable name).

And when you use parameter name:

PREPARE stmt FROM 'SELECT id INTO rid FROM t1';

in the string being prepared, then server simply do not know what that rid refers to in statement you are trying to prepare. You may try to prepare it outside SP with the same result:

mysql> prepare stmt from 'select id into p from t1';
ERROR 1327 (42000): Undeclared variable: p

So I just used user variable, see below:

DROP PROCEDURE IF EXISTS `singledb`.`TOUR_TRANSFER`$$

CREATE DEFINER=`root`@`localhost` PROCEDURE `TOUR_TRANSFER`()
BEGIN
  BEGIN -- for rubric table
    -- DECLARE @tblRubric_rubric_id INT;

    SET @tblRubric_rubric_id := 0;
    SET @qry = 'SELECT count(*) into @tblRubric_rubric_id FROM zerodb2.tour_template';
    PREPARE statement FROM @qry;
    EXECUTE statement;
  END;
END$$