Mysql concurrency: what happens if a locked table is accessed?

Posted by PixelSapiens on Stack Overflow See other posts from Stack Overflow or by PixelSapiens
Published on 2012-03-20T11:27:52Z Indexed on 2012/03/20 11:29 UTC
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mysql

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concurrency

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myisam

the question is rather simple but I couldn't find a precise answer: in a myisam db, what happens if a php file locks a table (with an atomic operation, say an INSERT) and another php file tries to access the same table (reading or writing)?

Now, while it is obvious that the second session will not be able to access the table, what exactly happens? Does it return some kind of error? Does is wait in queue until it is able to access it?

Thanks in advance!

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