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| author | Bruce Momjian <bruce@momjian.us> | 2002-08-10 20:43:46 +0000 |
|---|---|---|
| committer | Bruce Momjian <bruce@momjian.us> | 2002-08-10 20:43:46 +0000 |
| commit | 7dc40a2be053a11544c708f576f2bb2858f14aa9 (patch) | |
| tree | 589411a580c5b8e6f1349dd60f4c4b6d79ecbb84 /doc/src | |
| parent | 181ca96e7a730ba35e973d3361422e6d8a460f88 (diff) | |
| download | postgresql-7dc40a2be053a11544c708f576f2bb2858f14aa9.tar.gz postgresql-7dc40a2be053a11544c708f576f2bb2858f14aa9.zip | |
Major improvement in CLUSTER which preserves table characteristics using
relfilenode.
I sent the CLUSTER patch a few days ago and I think it was missed. I
append it again, this time including the regression test files. For the
committer, please note that you have to cvs add the files as they don't
exist. Maybe add to the parallel and serial schedules also, but I don't
know such stuff.
Alvaro Herrera (<alvherre[a]atentus.com>)
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ref/cluster.sgml | 36 |
1 files changed, 15 insertions, 21 deletions
diff --git a/doc/src/sgml/ref/cluster.sgml b/doc/src/sgml/ref/cluster.sgml index c8499ca0581..4600e9e7b91 100644 --- a/doc/src/sgml/ref/cluster.sgml +++ b/doc/src/sgml/ref/cluster.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.16 2002/04/23 02:07:15 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.17 2002/08/10 20:43:46 momjian Exp $ PostgreSQL documentation --> @@ -75,19 +75,6 @@ CLUSTER </varlistentry> <varlistentry> <term><computeroutput> -ERROR: relation <<replaceable class="PARAMETER">tablerelation_number</replaceable>> inherits "<replaceable class="PARAMETER">table</replaceable>" - </computeroutput></term> - <listitem> - <para> - <comment> - This is not documented anywhere. It seems not to be possible to - cluster a table that is inherited. - </comment> - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><computeroutput> ERROR: Relation <replaceable class="PARAMETER">table</replaceable> does not exist! </computeroutput></term> <listitem> @@ -139,13 +126,6 @@ ERROR: Relation <replaceable class="PARAMETER">table</replaceable> does not exis </title> <para> - The table is actually copied to a temporary table in index - order, then renamed back to the original name. For this - reason, all grant permissions and other indexes are lost - when clustering is performed. - </para> - - <para> In cases where you are accessing single rows randomly within a table, the actual order of the data in the heap table is unimportant. However, if you tend to access some @@ -194,6 +174,20 @@ SELECT <replaceable class="parameter">columnlist</replaceable> INTO TABLE <repla fast because most of the heap data has already been ordered, and the existing index is used. </para> + + <para> + During the cluster operation, a temporal table is created that contains + the table in the index order. Due to this, you need to have free space + on disk at least the size of the table itself, or the biggest index if + you have one that is larger than the table. + </para> + + <para> + As opposed to previous releases, CLUSTER does not lose GRANT, + inheritance or foreign key information, and preserves indexes + other than the one being used for the CLUSTER. + </para> + </refsect2> </refsect1> |