Re: JOIN migration from Oracle to MySQL

spikerlion@gmx.de wrote:
> Hello,
>
> thank you - now it works.
>
> d_parenttype PT1 LEFT OUTER JOIN t_booklists bl ON (PT1.ID = bl.PARENTTYPE_1),
> d_parenttype PT2 LEFT OUTER JOIN t_booklists bk ON (PT2.ID = bk.PARENTTYPE_2)
>
>
> I had to put the alias to all listet fields in the select.
>

Unless you are relating PT1 to PT2 in some way, you should not expect this query to perform well because you will be generating a Cartesian product between PT1 and PT2. I doubt this is actually what you are trying to do (although it will eventually work). If you posted just a few more details about the query you are trying to write, we could try to help you to rewrite it in a way that will perform much better than the translation you just attempted.

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