How do you debug MySQL stored procedures?

Question

My current process for debugging stored procedures is very simple. I create a table called \"debug\" where I insert variable values from the stored procedure as it runs. Thi

Answer 1

Yes, there is a specialized tools for this kind of thing - MySQL Debugger.

Answer 2

I'm late to the party, but brought more beer:

http://ocelot.ca/blog/blog/2015/03/02/the-ocelotgui-debugger/ and https://github.com/ocelot-inc/ocelotgui

I tried, and it seems pretty stable, supporting Breakpoints and Variable inspection.

It's not a complete suite (just 4,1 Mb) but helped me a lot!

How it works: It integrates with your mysql client (I'm using Ubuntu 14.04), and after you execute:

$install
$setup yourFunctionName

It installs a new database at your server, that control the debugging process. So:

$debug yourFunctionName('yourParameter')

will give you a chance to step by step walk your code, and "refreshing" your variables you can better view what is going on inside your code.

Important Tip: while debugging, maybe you will change (re-create the procedure). After a re-creation, execute: $exit and $setup before a new $debug

This is an alternative to "insert" and "log" methods. Your code remains free of additional "debug" instructions.

Screenshot:

Answer 3

Toad mysql. There is a freeware version http://www.quest.com/toad-for-mysql/

Answer 4

There are GUI tools for debugging stored procedures / functions and scripts in MySQL. A decent tool that dbForge Studio for MySQL, has rich functionality and stability.

Answer 5

Answer corresponding to this by @Brad Parks Not sure about the MySQL version, but mine was 5.6, hence a little bit tweaking works:

I created a function debug_msg which is function (not procedure) and returns text(no character limit) and then call the function as SELECT debug_msg(params) AS my_res_set, code as below:

CREATE DEFINER=`root`@`localhost` FUNCTION `debug_msg`(`enabled` INT(11), `msg` TEXT) RETURNS text CHARSET latin1
    READS SQL DATA
BEGIN
    IF enabled=1 THEN
    return concat('** DEBUG:', "** ", msg);
    END IF;
END

DELIMITER $$
CREATE DEFINER=`root`@`localhost` PROCEDURE `proc_func_call`(
 IN RegionID VARCHAR(20),
 IN RepCurrency INT(11),
 IN MGID INT(11),
 IN VNC VARCHAR(255)
)
BEGIN
    SET @enabled = TRUE;
    SET @mainQuery = "SELECT * FROM Users u";
    SELECT `debug_msg`(@enabled, @mainQuery) AS `debug_msg1`;
    SET @lastQuery = CONCAT(@mainQuery, " WHERE u.age>30);
    SELECT `debug_msg`(@enabled, @lastQuery) AS `debug_msg2`;
END $$
DELIMITER

Answer 6

Debugger for mysql was good but its not free. This is what i use now:

DELIMITER GO$

DROP PROCEDURE IF EXISTS resetLog

GO$

Create Procedure resetLog() 
BEGIN   
    create table if not exists log (ts timestamp default current_timestamp, msg varchar(2048)) engine = myisam; 
    truncate table log;
END; 

GO$

DROP PROCEDURE IF EXISTS doLog 

GO$

Create Procedure doLog(in logMsg nvarchar(2048))
BEGIN  
  insert into log (msg) values(logMsg);
END;

GO$

Usage in stored procedure:

call dolog(concat_ws(': ','@simple_term_taxonomy_id',  @simple_term_taxonomy_id));

usage of stored procedure:

call resetLog ();
call stored_proc();
select * from log;