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Clarify hash index caution and copy to CREATE INDEX docs

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Lines changed: 4 additions & 2 deletions

Original file line number	Diff line number	Diff line change
`@@ -196,8 +196,10 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>`
`196`	`196`	`<para>`
`197`	`197`	`Hash index operations are not presently WAL-logged,`
`198`	`198`	`so hash indexes might need to be rebuilt with <command>REINDEX</>`
`199`		`- after a database crash. They are also not replicated over streaming or`
`200`		`- file-based replication.`
	`199`	`+ after a database crash if there were unwritten changes.`
	`200`	`+ Also, changes to hash indexes are not replicated over streaming or`
	`201`	`+ file-based replication after the initial base backup, so they`
	`202`	`+ give wrong anwers to queries that subsequently use them.`
`201`	`203`	`For these reasons, hash index use is presently discouraged.`
`202`	`204`	`</para>`
`203`	`205`	`</caution>`

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Original file line number	Diff line number	Diff line change
`@@ -466,6 +466,18 @@ Indexes:`
`466`	`466`	`they can be useful.`
`467`	`467`	`</para>`
`468`	`468`
	`469`	`+ <caution>`
	`470`	`+ <para>`
	`471`	`+ Hash index operations are not presently WAL-logged,`
	`472`	`+ so hash indexes might need to be rebuilt with <command>REINDEX</>`
	`473`	`+ after a database crash if there were unwritten changes.`
	`474`	`+ Also, changes to hash indexes are not replicated over streaming or`
	`475`	`+ file-based replication after the initial base backup, so they`
	`476`	`+ give wrong anwers to queries that subsequently use them.`
	`477`	`+ For these reasons, hash index use is presently discouraged.`
	`478`	`+ </para>`
	`479`	`+ </caution>`
	`480`	`+`
`469`	`481`	`<para>`
`470`	`482`	`Currently, only the B-tree, GiST and GIN index methods support`
`471`	`483`	`multicolumn indexes. Up to 32 fields can be specified by default.`

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