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POHow to join two tables without messing up the query
 

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  1. POHow to join two tables without messing up the query
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    <p>I have this query for example (good, it works how I want it to)</p> <pre><code>SELECT `discusComments`.`memberID`, COUNT( `discusComments`.`memberID`) AS postcount FROM `discusComments` GROUP BY `discusComments`.`memberID` ORDER BY postcount DESC </code></pre> <p>Example Results:</p> <pre><code>memberid postcount 3 283 6 230 9 198 </code></pre> <p>Now I want to join the memberid of the discusComments table with that of the discusTopic table (because what I really want to do is only get my results from a specific GROUP, and the group id is only in the topic table and not in the comment one hence the join.</p> <pre><code>SELECT `discusComments`.`memberID`, COUNT( `discusComments`.`memberID`) AS postcount FROM `discusComments` LEFT JOIN `discusTopics` ON `discusComments`.`memberID` = `discusTopics`.`memberID` GROUP BY `discusComments`.`memberID` ORDER BY postcount DESC </code></pre> <p>Example Results:</p> <pre><code>memberid postcount 3 14789 6 8678 9 6987 </code></pre> <p>How can I stop this huge increase happening in the postcount? I need to preserve it as before.</p> <p>Once I have this sorted I want to have some kind of line which says <code>WHERE discusTopics.groupID = 6</code>, for example</p> <pre><code>CREATE TABLE IF NOT EXISTS `discusComments` ( `id` bigint(255) NOT NULL auto_increment, `topicID` bigint(255) NOT NULL, `comment` text NOT NULL, `timeStamp` bigint(12) NOT NULL, `memberID` bigint(255) NOT NULL, `thumbsUp` int(15) NOT NULL default '0', `thumbsDown` int(15) NOT NULL default '0', `status` int(1) NOT NULL default '1', PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=7190 ; </code></pre> <p>.</p> <pre><code>CREATE TABLE IF NOT EXISTS `discusTopics` ( `id` bigint(255) NOT NULL auto_increment, `groupID` bigint(255) NOT NULL, `memberID` bigint(255) NOT NULL, `name` varchar(255) NOT NULL, `views` bigint(255) NOT NULL default '0', `lastUpdated` bigint(10) NOT NULL, PRIMARY KEY (`id`), KEY `groupID` (`groupID`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=913 ; </code></pre>
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    1. USJake
    1. USJake
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    1. COAre the tables `discusComments` and `discusTopics` related to each other in any way other than by `MemberID`? Maybe the join condition you are using is just wrong (or incomplete).
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      1. POHow to join two tables without messing up the query
      1. USAndriy M
    2. COYou need to explain more about the tables and their relationships. It seems clear to me that each `memberID` has many records in the `discusTopics` table. But why, what does that table mean? And what are it's foreign keys and unique constraints. You mention that the table has a `groupID` field. Is `memberID, groupID` unique? If so, include `groupID` in your select an `GROUP BY` and see what you get.
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      1. POHow to join two tables without messing up the query
      1. USMatBailie
    3. COI've just added the structures
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      1. POHow to join two tables without messing up the query
      1. USJake
 

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