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Re: Server just hanging (Copying to tmp table)
Posted by: Jay Pipes
Date: December 15, 2005 02:14PM

Not a big deal. The best explanation I can give for when to use a LEFT JOIN is the following:

Use a left join when you have two sets of data, say set A and set B, that are related through some common field(s), and you want to have *all* rows of set A appear in your final result *regardless* of whether there is a matching row in set B. The "left" part of LEFT JOIN simply means the table (or dataset) on the *left* side of the ON expression, that's all.

HTH, and good to see everything's working OK.

Jay Pipes
Community Relations Manager, North America, MySQL Inc.

Got Cluster? http://www.mysql.com/cluster
Personal: http://jpipes.com

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