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Re: Optimising query with composite index, which says using where
Posted by: Øystein Grøvlen
Date: September 15, 2014 06:03AM

Hi,

In the given statement, index merge is of no use since there is only one condition in each query that does not match all rows.

Also, index merge may only be used for equality predicates. This is because it depends on rows returned from index to be in ROWID (primary key for InnoDB) order.

Øystein Grøvlen,
Senior Principal Software Engineer,
MySQL Group, Oracle,
Trondheim, Norway

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Optimising query with composite index, which says using where
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Timothy Mifsud
September 06, 2014 12:38AM
Re: Optimising query with composite index, which says using where
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Timothy Mifsud
September 06, 2014 01:53AM
Re: Optimising query with composite index, which says using where
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Rick James
September 07, 2014 10:46PM
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Øystein Grøvlen
September 15, 2014 06:03AM
Re: Optimising query with composite index, which says using where
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Rick James
September 15, 2014 10:03AM


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