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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
`@@ -191,8 +191,10 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>`
`191`	`191`	`<para>`
`192`	`192`	`Hash index operations are not presently WAL-logged,`
`193`	`193`	`so hash indexes might need to be rebuilt with <command>REINDEX</>`
`194`		`- after a database crash. They are also not replicated over streaming or`
`195`		`- file-based replication.`
	`194`	`+ after a database crash if there were unwritten changes.`
	`195`	`+ Also, changes to hash indexes are not replicated over streaming or`
	`196`	`+ file-based replication after the initial base backup, so they`
	`197`	`+ give wrong anwers to queries that subsequently use them.`
`196`	`198`	`For these reasons, hash index use is presently discouraged.`
`197`	`199`	`</para>`
`198`	`200`	`</caution>`

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Original file line number	Diff line number	Diff line change
`@@ -439,6 +439,18 @@ Indexes:`
`439`	`439`	`they can be useful.`
`440`	`440`	`</para>`
`441`	`441`
	`442`	`+ <caution>`
	`443`	`+ <para>`
	`444`	`+ Hash index operations are not presently WAL-logged,`
	`445`	`+ so hash indexes might need to be rebuilt with <command>REINDEX</>`
	`446`	`+ after a database crash if there were unwritten changes.`
	`447`	`+ Also, changes to hash indexes are not replicated over streaming or`
	`448`	`+ file-based replication after the initial base backup, so they`
	`449`	`+ give wrong anwers to queries that subsequently use them.`
	`450`	`+ For these reasons, hash index use is presently discouraged.`
	`451`	`+ </para>`
	`452`	`+ </caution>`
	`453`	`+`
`442`	`454`	`<para>`
`443`	`455`	`Currently, only the B-tree, GiST and GIN index methods support`
`444`	`456`	`multicolumn indexes. Up to 32 fields can be specified by default.`

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