I need some help joining data from 3 MySQL tables, please

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Hi all,

I am trying to display collective data from 3 MySQL tables:

The query I have, so far, is

SELECT c . * , COUNT( m.id ) AS `members`
FROM `jos_mls_teams` AS `c`
LEFT JOIN `jos_mls_teams_members` AS `m` ON m.teamid = c.id
RIGHT JOIN (
SELECT u.name, u.lastvisitDate FROM `jos_users` AS `u` )
ON u.id = m.userid
GROUP BY c.id
LIMIT 0 , 30

But get the following error:

#1248 - Every derived table must have its own alias

 

A google search results suggested the alias should be put after the bracket. So, I change the code as follow, and move the AS `u` outside the right bracket:

 SELECT c . * , COUNT( m.id ) AS `members`
FROM `jos_mls_teams` AS `c`
LEFT JOIN `jos_mls_teams_members` AS `m` ON m.teamid = c.id
RIGHT JOIN (
SELECT u.name, u.lastvisitDate FROM `jos_users` ) AS `u`
ON u.id = m.userid
GROUP BY c.id
LIMIT 0 , 30
 

But then I get the error:

 #1054 - Unknown column 'u.name' in 'field list' 

 

Basically, I need to display all the data from the "jos_mls_teams", total number of members linked to a user from the "jos_mls_teams_members" (basically counting all the rows where the corresponding user's id is in the userid field. Then I want to display that same corresponding user's name & email from another table.

 

Table structures to follow:

 

CREATE TABLE `jos_mls_teams` (
  `id` int(11) NOT NULL auto_increment,
  `userid` int(5) NOT NULL,
  `memberid` int(11) NOT NULL,
  `name` varchar(255) NOT NULL default '',
  `email` text,
  `area` text,
  `arealeader` varchar(150) NOT NULL,
  `founded` text,
  `herder` varchar(100) NOT NULL,
  PRIMARY KEY  (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=19 ;

 

 
CREATE TABLE IF NOT EXISTS `jos_users` (
  `id` int(11) NOT NULL auto_increment,
  `name` varchar(255) NOT NULL default '',
  `username` varchar(150) NOT NULL default '',
  `email` varchar(100) NOT NULL default '',
  `password` varchar(100) NOT NULL default '',
  `usertype` varchar(25) NOT NULL default '',
  `block` tinyint(4) NOT NULL default '0',
  `sendEmail` tinyint(4) default '0',
  `gid` tinyint(3) unsigned NOT NULL default '1',
  `registerDate` datetime NOT NULL default '0000-00-00 00:00:00',
  `lastvisitDate` datetime NOT NULL default '0000-00-00 00:00:00',
  `activation` varchar(100) NOT NULL default '',
  `params` text NOT NULL,
  PRIMARY KEY  (`id`),
  KEY `usertype` (`usertype`),
  KEY `idx_name` (`name`),
  KEY `gid_block` (`gid`,`block`),
  KEY `username` (`username`),
  KEY `email` (`email`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=73 ;

 

CREATE TABLE IF NOT EXISTS `jos_mls_teams_members` (
  `id` int(11) NOT NULL auto_increment,
  `teamid` int(11) NOT NULL default '0',
  `userid` int(11) NOT NULL default '0',
  `leader` tinyint(1) NOT NULL default '0',
  `sysid` int(11) NOT NULL,
  `memberid` int(11) NOT NULL,
  PRIMARY KEY  (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=29  

 

P.S. just to be clear, I want to eventually remove the name & email fields from the `jos_mls_teams` table, since Joomla uses the `jos_users` table for registration purposes and it's easier to use the built-in registration than trying to reinvent the wheel :)



--
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532
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