Commit0915d37

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

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Lines changed: 3 additions & 9 deletions

Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`
`2`	`2`	`Frequently Asked Questions (FAQ) for PostgreSQL`
`3`	`3`
`4`		`- Last updated:Sun Feb12 12:15:49 EST 2006`
	`4`	`+ Last updated:Fri Feb24 09:59:35 EST 2006`
`5`	`5`
`6`	`6`	`Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)`
`7`	`7`
`@@ -569,14 +569,8 @@`
`569`	`569`	`sequential scan followed by an explicit sort is usually faster than an`
`570`	`570`	`index scan of a large table.`
`571`	`571`	`However, LIMIT combined with ORDER BY often will use an index because`
`572`		`- only a small portion of the table is returned. In fact, though MAX()`
`573`		`- and MIN() don't use indexes, it is possible to retrieve such values`
`574`		`- using an index with ORDER BY and LIMIT:`
`575`		`- SELECT col`
`576`		`- FROM tab`
`577`		`- ORDER BY col [ DESC ]`
`578`		`- LIMIT 1;`
`579`		`-`
	`572`	`+ only a small portion of the table is returned.`
	`573`	`+`
`580`	`574`	`If you believe the optimizer is incorrect in choosing a sequential`
`581`	`575`	`scan, use SET enable_seqscan TO 'off' and run query again to see if an`
`582`	`576`	`index scan is indeed faster.`

Lines changed: 3 additions & 11 deletions

Original file line number	Diff line number	Diff line change
`@@ -10,7 +10,7 @@`
`10`	`10`	`alink="#0000ff">`
`11`	`11`	`<H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>`
`12`	`12`
`13`		`-<P>Last updated:Sun Feb12 12:15:49 EST 2006</P>`
	`13`	`+<P>Last updated:Fri Feb24 09:59:35 EST 2006</P>`
`14`	`14`
`15`	`15`	`<P>Current maintainer: Bruce Momjian (<Ahref=`
`16`	`16`	`"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)`
`@@ -742,16 +742,8 @@ <H3 id="item4.6">4.6) Why are my queries slow? Why don't they`
`742`	`742`	`usually faster than an index scan of a large table.</P>`
`743`	`743`	`However,<SMALL>LIMIT</SMALL> combined with<SMALL>ORDER BY</SMALL>`
`744`	`744`	`often will use an index because only a small portion of the table`
`745`		`- is returned. In fact, though MAX() and MIN() don't use indexes,`
`746`		`- it is possible to retrieve such values using an index with ORDER BY`
`747`		`- and LIMIT:`
`748`		`-<PRE>`
`749`		`- SELECT col`
`750`		`- FROM tab`
`751`		`- ORDER BY col [ DESC ]`
`752`		`- LIMIT 1;`
`753`		`-</PRE>`
`754`		`-`
	`745`	`+ is returned.</P>`
	`746`	`+`
`755`	`747`	`<P>If you believe the optimizer is incorrect in choosing a`
`756`	`748`	`sequential scan, use<CODE>SET enable_seqscan TO 'off'</CODE> and`
`757`	`749`	`run query again to see if an index scan is indeed faster.</P>`

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