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<TITLE>Respect your server's SQL cache</TITLE>
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<H1>Respect your server's SQL cache</H1>
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<LI><H2>Optimised Access Plan etc. is cached within the server
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<LI>keyed by the exact original SQL string used
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<LI><H2>Compare do("insert
$id");
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with do("insert
?", undef, $id);
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<LI><H2>Without placeholders, SQL string varies each time
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<LI>so cached one is not reused
<LI>so time is wasted creating a new access plan
<LI>the new statement and access plan are added to cache
<LI>so the cache fills and other statements get pushed out
<LI>on a busy system this can lead to thrashing
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<H2>.</H2>
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