At 7:22 AM +0800 11/12/99, Orlando Andico wrote:
>does SELECT SUM() lock the entire table? I'm seeing very slow queries due
>to multiple SELECT SUM()'s and a few UPDATEs here and there running
>concurrently. Or am I just hitting a limitation of MySQL?
When MySQL accesses a table, it acquires a table-level lock for
you, yes. A read lock will lock out all queries that are trying
to write to the table, until the SELECT has finished.
>
>I've already used INSERT DELAYED for everything to reduce the write
>contention..
--
Paul DuBois, paul@stripped