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Commit 0915d37

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Remove mention of MIN/MAX() not using indexes.
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doc/FAQ

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Frequently Asked Questions (FAQ) for PostgreSQL
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Last updated: Sun Feb 12 12:15:49 EST 2006
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Last updated: Fri Feb 24 09:59:35 EST 2006
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Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
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sequential scan followed by an explicit sort is usually faster than an
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index scan of a large table.
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However, LIMIT combined with ORDER BY often will use an index because
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only a small portion of the table is returned. In fact, though MAX()
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and MIN() don't use indexes, it is possible to retrieve such values
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using an index with ORDER BY and LIMIT:
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SELECT col
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FROM tab
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ORDER BY col [ DESC ]
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LIMIT 1;
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only a small portion of the table is returned.
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If you believe the optimizer is incorrect in choosing a sequential
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scan, use SET enable_seqscan TO 'off' and run query again to see if an
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index scan is indeed faster.

doc/src/FAQ/FAQ.html

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alink="#0000ff">
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<H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>
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<P>Last updated: Sun Feb 12 12:15:49 EST 2006</P>
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<P>Last updated: Fri Feb 24 09:59:35 EST 2006</P>
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<P>Current maintainer: Bruce Momjian (<A href=
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"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)
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usually faster than an index scan of a large table.</P>
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However, <SMALL>LIMIT</SMALL> combined with <SMALL>ORDER BY</SMALL>
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often will use an index because only a small portion of the table
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is returned. In fact, though MAX() and MIN() don't use indexes,
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it is possible to retrieve such values using an index with ORDER BY
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and LIMIT:
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<PRE>
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SELECT col
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FROM tab
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ORDER BY col [ DESC ]
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LIMIT 1;
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</PRE>
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is returned.</P>
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<P>If you believe the optimizer is incorrect in choosing a
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sequential scan, use <CODE>SET enable_seqscan TO 'off'</CODE> and
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run query again to see if an index scan is indeed faster.</P>

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