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Re: Cross table access query
Posted by: Peter Brawley
Date: July 21, 2014 08:52AM

> When you say hero_id_index, what is that representing?

hero_id_1 &c is a design mistake. As a rule of thumb, when you find yourself creating columns with _1, _2 &c suffixes, stop, because it's inefficient and messes up querying. There should be one hero_id column. Your _1 _2 and _3 indexicals need to be in their own column. To understand why, read about normalisation.

> I don't understand what the m and h are in the query.

Those are aliases, ie conveniences for simplifying query reading & writing. See the manual for query syntax (or any introductory sql text).

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July 20, 2014 05:42PM
July 20, 2014 08:50PM
July 20, 2014 11:56PM
Re: Cross table access query
July 21, 2014 08:52AM
July 21, 2014 10:40AM


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