CODEWITHSUNDEEP
mysqlstored-procedures
ducin
ducin

Reputation: 26437

mysql stored procedure set value from table

I've got a following, simple table:

mysql> select * from version;
+----+---------+
| id | version |
+----+---------+
|  1 | 1       |
+----+---------+
1 row in set (0.00 sec)

I need to create a stored procedure that will do something (or nothing) depending on the value of this table (precisely, the only row of this table).

DELIMITER $$
DROP PROCEDURE IF EXISTS upgrade_version $$
CREATE PROCEDURE upgrade_version(current_version INTEGER, script TEXT)
BEGIN
  DECLARE version INT(11);
  SET version = (SELECT `version` FROM `version` WHERE `id` = 1 LIMIT 1);
  SELECT version;
  IF version = current_version + 1 THEN
    PREPARE upgrade_stmt FROM script;
    EXECUTE upgrade_stmt;
    UPDATE `version` SET `version` = `version` + 1 WHERE `id` = 1;
  ENDIF;
END $$
DELIMITER ;

To be called within:

CALL upgrade_version(1,'ALTER TABLE ...');

It is syntactically incorrect, mysql returns:

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 'script;
    EXECUTE upgrade_stmt;
    UPDATE `version` SET `version` = `version`' at line 7

What is wrong?

Upvotes: 3

Views: 21200

Answers (3)

Hari Lakkakula
Hari Lakkakula

Reputation: 307

Set Value To Declare variable

       DELIMITER $$
       create procedure Testing()
           begin
            declare Regione int;   
            set Regione=(select  id from users
            where id=1) ;
            select Regione ;
           end $$
         DELIMITER;

Upvotes: 0

Chella
Chella

Reputation: 1562

I dont understand why you are selecting that "SELECT version", If you want to select the data you have to retrieve it into a varialbe, that statement works fine when you use it directly at the terminal. And are you sure that you have prepared_stmt in your scripts..!? possible fix is :

  1. change the varible name version to version_v

  2. instead of this:

    SET version = (SELECT version FROM version WHERE id = 1 LIMIT 1);
    SELECT version;

try this: 

SELECT `version` INTO Version_v FROM `version` WHERE `id` = 1 LIMIT 1);

Upvotes: 5

Saharsh Shah
Saharsh Shah

Reputation: 29051

Try this: 

DELIMITER $$
DROP PROCEDURE IF EXISTS upgrade_version $$
CREATE PROCEDURE upgrade_version(current_version INT, script TEXT)
BEGIN
  SELECT `version` into @ver FROM `version` WHERE `id` = 1 LIMIT 1;  
  SET @s = script;
  IF @ver = current_version + 1 THEN
    PREPARE upgrade_stmt FROM @s;
    EXECUTE upgrade_stmt;
    DEALLOCATE PREPARE upgrade_stmt;
    UPDATE `version` SET `version` = `version` + 1 WHERE `id` = 1;
  END IF;
END $$
DELIMITER ;

Upvotes: 4

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