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 :)
Rudi Ahlers wrote:
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 http://u.name' in 'field list'
Inside the subquery, the table is jos_users (and since there is only one you shouldn't even have to specify it. The 'u' alias is a temporary table holding the result from the subquery.