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Rearrange documentation paragraph describing pg_relation_size().

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Break the list of available options into an <itemizedlist> instead of
inline sentences.  This is mostly motivated by wanting to ensure that the
cross-references to the FSM and VM docs don't cross page boundaries in PDF
format; but it seems to me to read more easily this way anyway.  I took the
liberty of editorializing a bit further while at it.

Per complaint from Magnus about 9.0.18 docs not building in A4 format.
Patch all active branches so we don't get blind-sided by this particular
issue again in future.
This commit is contained in:
Tom Lane 2014-07-23 15:20:31 -04:00
parent 0ea1f2a3a8
commit 4fd9e6ffdd
1 changed files with 34 additions and 14 deletions
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doc/src/sgml/func.sgml
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@ -16928,20 +16928,40 @@ postgres=# SELECT * FROM pg_xlogfile_name_offset(pg_stop_backup());
</para>
<para>
<function>pg_relation_size</> accepts the OID or name of a table, index or
toast table, and returns the on-disk size in bytes.
Specifying <literal>'main'</literal> or leaving out the second argument
returns the size of the main data fork of the relation.
Specifying <literal>'fsm'</literal> returns the size of the Free Space
Map (see <xref linkend="storage-fsm">) associated with the relation.
Specifying <literal>'vm'</literal> returns the size of the Visibility
Map (see <xref linkend="storage-vm">) associated with the relation.
Specifying <literal>'init'</literal> returns the size of the
initialization fork, if any, associated with the relation.
Note that this function shows the size of only one fork;
for most purposes it is more convenient to use the higher-level
functions <function>pg_total_relation_size</> or
<function>pg_table_size</>.
<function>pg_relation_size</> accepts the OID or name of a table, index
or toast table, and returns the on-disk size in bytes of one fork of
that relation. (Note that for most purposes it is more convenient to
use the higher-level functions <function>pg_total_relation_size</>
or <function>pg_table_size</>, which sum the sizes of all forks.)
With one argument, it returns the size of the main data fork of the
relation. The second argument can be provided to specify which fork
to examine:
<itemizedlist spacing="compact">
<listitem>
<para>
<literal>'main'</literal> returns the size of the main
data fork of the relation.
</para>
</listitem>
<listitem>
<para>
<literal>'fsm'</literal> returns the size of the Free Space Map
(see <xref linkend="storage-fsm">) associated with the relation.
</para>
</listitem>
<listitem>
<para>
<literal>'vm'</literal> returns the size of the Visibility Map
(see <xref linkend="storage-vm">) associated with the relation.
</para>
</listitem>
<listitem>
<para>
<literal>'init'</literal> returns the size of the initialization
fork, if any, associated with the relation.
</para>
</listitem>
</itemizedlist>
</para>
<para>