<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.496 2010/01/15 09:18:58 heikki Exp $ -->

<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.497 2010/01/19 05:50:18 tgl Exp $ -->

<chapter id="functions">

<title>Functions and Operators</title>

</entry>

<entry><type>text</type></entry>

<entry>Get last transaction log location received and synced to disk during

streaming recovery. If streaming recovery is still in progress

this will increase monotonically. If streaming recovery has completed

then this value will remain static at the value of the last WAL record

received and synced to disk during that recovery. When the server has

been started without a streaming recovery then the return value will be

InvalidXLogRecPtr (0/0).

streaming recovery. If streaming recovery is still in progress

this will increase monotonically. If streaming recovery has completed

then this value will remain static at the value of the last WAL record

received and synced to disk during that recovery. When the server has

been started without a streaming recovery then the return value will be

InvalidXLogRecPtr (0/0).

</entry>

</row>

<row>

</entry>

<entry><type>text</type></entry>

<entry>Get last transaction log location replayed during recovery.

If recovery is still in progress this will increase monotonically.

If recovery has completed then this value will remain static at

the value of the last WAL record applied during that recovery.

When the server has been started normally without a recovery

then the return value will be InvalidXLogRecPtr (0/0).

If recovery is still in progress this will increase monotonically.

If recovery has completed then this value will remain static at

the value of the last WAL record applied during that recovery.

When the server has been started normally without a recovery

then the return value will be InvalidXLogRecPtr (0/0).

</entry>

</row>

</tbody>

<primary>pg_column_size</primary>

</indexterm>

<indexterm>

<primary>pg_database_size</primary>

<primary>pg_total_relation_size</primary>

</indexterm>

<indexterm>

<primary>pg_relation_size</primary>

<primary>pg_table_size</primary>

</indexterm>

<indexterm>

<primary>pg_size_pretty</primary>

<primary>pg_indexes_size</primary>

</indexterm>

<indexterm>

<primary>pg_database_size</primary>

</indexterm>

<indexterm>

<primary>pg_tablespace_size</primary>

</indexterm>

<indexterm>

<primary>pg_total_relation_size</primary>

<primary>pg_relation_size</primary>

</indexterm>

<indexterm>

<primary>pg_size_pretty</primary>

</indexterm>

<table id="functions-admin-dbsize">

</row>

<row>

<entry>

<literal><function>pg_database_size</function>(<type>oid</type>)</literal>

<literal><function>pg_total_relation_size</function>(<type>regclass</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>Disk space used by the database with the specified OID</entry>

<entry>

Total disk space used by the table with the specified OID or name,

including all indexes and <acronym>TOAST</> data

</entry>

</row>

<row>

<entry>

<literal><function>pg_database_size</function>(<type>name</type>)</literal>

<literal><function>pg_table_size</function>(<type>regclass</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>Disk space used by the database with the specified name</entry>

<entry>

Disk space used by the table with the specified OID or name,

excluding indexes (but including TOAST, free space map, and visibility

map)

</entry>

</row>

<row>

<entry>

<literal><function>pg_relation_size</function>(<parameter>relation</parameter> <type>regclass</type>, <parameter>fork</parameter> <type>text</type>)</literal>

<literal><function>pg_indexes_size</function>(<type>regclass</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>

Disk space used by the specified fork (<literal>'main'</literal>,

<literal>'fsm'</literal> or <literal>'vm'</>)

of the table or index with the specified OID or name

Total disk space used by indexes attached to the table with the

specified OID or name

</entry>

</row>

<row>

<entry>

<literal><function>pg_relation_size</function>(<parameter>relation</parameter> <type>regclass</type>)</literal>

<literal><function>pg_database_size</function>(<type>oid</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>

Shorthand for <literal>pg_relation_size(..., 'main')</literal>

</entry>

<entry>Disk space used by the database with the specified OID</entry>

</row>

<row>

<entry>

<literal><function>pg_size_pretty</function>(<type>bigint</type>)</literal>

<literal><function>pg_database_size</function>(<type>name</type>)</literal>

</entry>

<entry><type>text</type></entry>

<entry>Converts a size in bytes into a human-readable formatwithsize units</entry>

<entry><type>bigint</type></entry>

<entry>Disk space used by the databasewiththe specified name</entry>

</row>

<row>

<entry>

</row>

<row>

<entry>

<literal><function>pg_total_relation_size</function>(<type>regclass</type>)</literal>

<literal><function>pg_relation_size</function>(<parameter>relation</parameter> <type>regclass</type>, <parameter>fork</parameter> <type>text</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>

Total disk space used by the table with the specified OID or name,

including indexes and <acronym>TOAST</> data

Disk space used by the specified fork (<literal>'main'</literal>,

<literal>'fsm'</literal> or <literal>'vm'</>)

of the table or index with the specified OID or name

</entry>

</row>

<row>

<entry>

<literal><function>pg_relation_size</function>(<parameter>relation</parameter> <type>regclass</type>)</literal>

</entry>

<entry><type>bigint</type></entry>

<entry>

Shorthand for <literal>pg_relation_size(..., 'main')</literal>

</entry>

</row>

<row>

<entry>

<literal><function>pg_size_pretty</function>(<type>bigint</type>)</literal>

</entry>

<entry><type>text</type></entry>

<entry>Converts a size in bytes into a human-readable format with size units</entry>

</row>

</tbody>

</tgroup>

</table>

data value.

</para>

<para>

<function>pg_total_relation_size</> accepts the OID or name of a

table or toast table, and returns the total on-disk space used for

that table, including all associated indexes. This function is

equivalent to <function>pg_table_size</function>

<literal>+</> <function>pg_indexes_size</function>.

</para>

<para>

<function>pg_table_size</> accepts the OID or name of a table and

returns the disk space needed for that table, exclusive of indexes.

(TOAST space, free space map, and visibility map are included.)

</para>

<para>

<function>pg_indexes_size</> accepts the OID or name of a table and

returns the total disk space used by all the indexes attached to that

table.

</para>

<para>

<function>pg_database_size</function> and <function>pg_tablespace_size</>

accept the OID or name of a database or tablespace, and return the total

<para>

<function>pg_relation_size</> accepts the OID or name of a table, index or

toast table, and returns the size in bytes. Specifying

toast table, and returns theon-disksize 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.

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</>.

</para>

<para>

appropriate.

</para>

<para>

<function>pg_total_relation_size</> accepts the OID or name of a

table or toast table, and returns the size in bytes of the data

and all associated indexes and toast tables.

</para>

<para>

The functions shown in <xref

linkend="functions-admin-genfile"> provide native access to