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Re: Filesort and big LOAD on top
Posted by: Rick James
Date: September 22, 2009 09:14AM

The best it can do is:
1. Find all rows with "linux" (because of +)
2. Ignore (or wast time on) ">debian", since the you don't care about the score
3. Filter on %iso%
4. After gathering all such rows, sort by "seeds" (ORDER BY); here's the filesort.
5. Deliver the first 50 (LIMIT)

Without the ORDER BY...
4. --
5. Deliver all the rows, in any order. (Hmmm... Or does it use the fulltext order, by default?)

To assist in analyzing slow SELECTs, please provide
* SHOW CREATE TABLE tbl\G -- engine, indexes
* SHOW TABLE STATUS LIKE 'tbl'\G -- sizes
* EXPLAIN SELECT ...\G -- clues of inefficiencies
* SHOW VARIABLES LIKE '%buffer%'; -- cache size
and surround them with [ code ] and [ / code ]

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Re: Filesort and big LOAD on top
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