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POHow can I speed up this giant query against a MyISAM table?
 

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  1. POHow can I speed up this giant query against a MyISAM table?
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    <p>This query goes against a single table. The table has 60 attributes called "attribute1" through "attribute60", and they are all of type:</p> <pre><code>varchar(255) </code></pre> <p>There is also a column called "brand_id" that is:</p> <pre><code>int(11) </code></pre> <p>The following key exists on the table:</p> <pre><code>brand_id, attribute1, attribute2, attribute3 </code></pre> <p>The query is as follows:</p> <pre><code>SELECT distinct attribute1 from brands b inner join product_applications pa on pa.brand_id = b.id where b.id in (1,372,373,374,375,376,378,381,452, 453,454,455,456,457,458,461,474,476, 544,480,563,508,512,513,516,517,519,520,521, 522,524,525,527,528,529,533,538,539,540,542, 546,547,548,555,556,557,642,643,644,645,646, 647,648,649,650,651,652,653,654,655) </code></pre> <p>It takes over 10 seconds. The table has 5,735,673 rows.</p> <p>This query needs to take no more than 2 seconds. I cannot figure out how to write it, or if I need some sort of alternate table structure, to do this. Can anyone offer a recommendation?</p> <p>I used to use an IN in the WHERE clause, but it was recommended in another forum that this ugly way was faster because of the join. I don't really know what that means, but it IS faster, but still incredibly slow.</p> <pre> +----+-------------+-------+-------+----------------------------------------+--------------------+---------+-----------+-------+-------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+----------------------------------------+--------------------+---------+-----------+-------+-------------------------------------------+ | 1 | SIMPLE | b | range | PRIMARY | PRIMARY | 4 | NULL | 60 | Using where; Using index; Using temporary | | 1 | SIMPLE | pa | ref | brand_search_index,parttype_search_idx | brand_search_index | 5 | mcp5.b.id | 57356 | Using where; Using index | +----+-------------+-------+-------+----------------------------------------+--------------------+---------+-----------+-------+-------------------------------------------+ 2 rows in set (0.04 sec) </pre>
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      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USPervez Choudhury
    1. USAKWF
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    1. VO
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. USribram
      1. VTFavorite
    2. VO
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. This table or related slice is empty.
      1. VTDownMod
    3. VO
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COUgh... Is there no way you can change this 1. to use InnoDB, and 2. to have a sane schema?
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. UScwallenpoole
    2. COHow many of the 5million rows in table PA are returned by the query if you leave the DISTINCT out of it?
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. USTim
    3. COHow will InnoDB speed up the query? Why is that table not sane? The variation among all of the attributes is such that it results in lots of rows, and yet is not so uniform that it can be broken up relationally.
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      1. POHow can I speed up this giant query against a MyISAM table?
      1. USAKWF
 

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