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PostgreSQL documentation

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</varlistentry>

<varlistentry>

<term><computeroutput>

ERROR: relation &lt;<replaceable class="PARAMETER">tablerelation_number</replaceable>&gt; 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>

Notes

</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

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>