What are JOINs in SQL (for)?

Posted by sabwufer on Stack Overflow See other posts from Stack Overflow or by sabwufer
Published on 2010-03-26T16:09:54Z Indexed on 2010/03/26 16:13 UTC
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I have been using MySQL for 2 years now, yet I still don't know what you actually do with the JOIN statement. I really didn't come across any situation where I was unable to solve a problem with the statements and syntax I already know (SELECT, INSERT, UPDATE, ordering, ...)

What does JOIN do in MySQL?
(Where) Do I need it?
Should I generally avoid it?

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