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From:ighen Date:June 15 2004 9:17am
Subject:performance with joins
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I have 3 tables:
    - table_1 - pri key is id+lang
    - table_2 - pri key is id
    - table_3 - pri key is id+lang (Full-Text table)
To join all 3 tables with their keys and run a full-text query, I understand I need to put
the Full-Text table at the end of the joins..
If I use the tables as defined above, then the join would be:

    ... FROM table_1 INNER JOIN table_2 ON table_1.id=table_2.id INNER JOIN table_3 ON
table_2.id=table_3.id AND table_1.lang=table_3.lang WHERE ...

The last join uses a primary key from both table_1 and table_2.. is that slower than a
case that table_2 key would be id+lang (which then the last join would use id+lang from
table_2 alone) ???


-thanks, Lorderon.

Thread
performance with joinsighen15 Jun
Re: performance with joinsSGreen15 Jun