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Two general MySQL questions
Posted by: Joost
Date: January 02, 2007 09:24AM

Hi,

1. When using SQL_CALC_FOUND_ROWS combined with a LIMIT and an ORDER BY. Does MySQL stop ordering after the LIMIT is reached? Or are all results ordered by MySQL while getting the SQL_CALC_FOUND_ROWS?
If this is the case it probably is faster to do a SELECT COUNT(*) instead..without an ORDER BY.

2. When MySQL (regular INNER??) JOINs two tables.. Does it first do a SELECT on table1 and a SELECT on table2 and then combine the results? Or does it do a SELECT on table1, join it.. and do another select?

Thanks!

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