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POSuper slow query with CROSS JOIN
 

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  1. POSuper slow query with CROSS JOIN
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    <p>I have two tables named table_1 (1GB) and reference (250Mb). </p> <p>When I query a cross join on reference it takes 16hours to update table_1 .. We changed the system files EXT3 for XFS but still it's taking 16hrs.. WHAT AM I DOING WRONG??</p> <p>Here is the update/cross join query : </p> <pre><code> mysql&gt; UPDATE table_1 CROSS JOIN reference ON -&gt; (table_1.start &gt;= reference.txStart AND table_1.end &lt;= reference.txEnd) -&gt; SET table_1.name = reference.name; Query OK, 17311434 rows affected (16 hours 36 min 48.62 sec) Rows matched: 17311434 Changed: 17311434 Warnings: 0 </code></pre> <p>Here is a show create table of table_1 and reference:</p> <pre><code> CREATE TABLE `table_1` ( `strand` char(1) DEFAULT NULL, `chr` varchar(10) DEFAULT NULL, `start` int(11) DEFAULT NULL, `end` int(11) DEFAULT NULL, `name` varchar(255) DEFAULT NULL, `name2` varchar(255) DEFAULT NULL, KEY `annot` (`start`,`end`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ; CREATE TABLE `reference` ( `bin` smallint(5) unsigned NOT NULL, `name` varchar(255) NOT NULL, `chrom` varchar(255) NOT NULL, `strand` char(1) NOT NULL, `txStart` int(10) unsigned NOT NULL, `txEnd` int(10) unsigned NOT NULL, `cdsStart` int(10) unsigned NOT NULL, `cdsEnd` int(10) unsigned NOT NULL, `exonCount` int(10) unsigned NOT NULL, `exonStarts` longblob NOT NULL, `exonEnds` longblob NOT NULL, `score` int(11) DEFAULT NULL, `name2` varchar(255) NOT NULL, `cdsStartStat` enum('none','unk','incmpl','cmpl') NOT NULL, `cdsEndStat` enum('none','unk','incmpl','cmpl') NOT NULL, `exonFrames` longblob NOT NULL, KEY `chrom` (`chrom`,`bin`), KEY `name` (`name`), KEY `name2` (`name2`), KEY `annot` (`txStart`,`txEnd`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ; </code></pre>
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    1. PO
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. USmadkitty
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    2. PO
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    3. PO
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    1. VO
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      1. POSuper slow query with CROSS JOIN
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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    3. VO
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      1. POSuper slow query with CROSS JOIN
      1. USKarolis
      1. VTFavorite
    1. COThe tables do not have Primary Keys?
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      1. USypercubeᵀᴹ
    2. COThere is no need to SHOUT in your question title....
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      1. USslugster
    3. COwhere did I shout in my question title??
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      1. USmadkitty
 

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