Mulit-column key and SELECT query

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#1136

From: Tumurbaatar S.
Date: Fri, 21 Jan 2005 08:42

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A table contains a primary key like this:

PRIMARY KEY (col1, col2,...colN)

And SELECT query like:

SELECT ... WHERE col1 op ? AND col2 op ? AND ... colN op ?

where "op" is some comparison operator (=,<>,>,<...).

Does MySQL use above key to optimize this query? Or I need
to create additional indexes on all fields except col1?

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Subject: Mulit-column key and SELECT query
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