diff options
author | Tom Lane <tgl@sss.pgh.pa.us> | 2005-08-02 16:11:57 +0000 |
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committer | Tom Lane <tgl@sss.pgh.pa.us> | 2005-08-02 16:11:57 +0000 |
commit | 0001e98d54f3d81c2ff413e4aec4933bd1378963 (patch) | |
tree | ccb54cc3cfd35c19b0386c08c160a50c05ce3aee /doc/src | |
parent | f023fc6689bae02908e73c4cd7cf6e98c09ce9d7 (diff) | |
download | postgresql-0001e98d54f3d81c2ff413e4aec4933bd1378963.tar.gz postgresql-0001e98d54f3d81c2ff413e4aec4933bd1378963.zip |
Code and docs review for pg_column_size() patch.
Diffstat (limited to 'doc/src')
-rw-r--r-- | doc/src/sgml/func.sgml | 109 |
1 files changed, 65 insertions, 44 deletions
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index ba372618ac8..7dc9a3b5978 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.275 2005/07/30 22:53:15 tgl Exp $ +$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.276 2005/08/02 16:11:56 tgl Exp $ PostgreSQL documentation --> @@ -2207,14 +2207,6 @@ PostgreSQL documentation </row> <row> - <entry><literal><function>pg_column_size</function>(<parameter>string</parameter>)</literal></entry> - <entry><type>integer</type></entry> - <entry>Number of bytes required to store the value, which might be compressed</entry> - <entry><literal>pg_column_size('jo\\000se'::bytea)</literal></entry> - <entry><literal>5</literal></entry> - </row> - - <row> <entry><literal><function>position</function>(<parameter>substring</parameter> in <parameter>string</parameter>)</literal></entry> <entry><type>integer</type></entry> <entry>Location of specified substring</entry> @@ -9181,11 +9173,29 @@ SELECT set_config('log_statement_stats', 'off', false); </para> <para> - The functions shown in <xref - linkend="functions-admin-dbsize"> calculate the actual disk space - usage of database objects. + The functions shown in <xref linkend="functions-admin-dbsize"> calculate + the actual disk space usage of database objects. </para> + <indexterm zone="functions-admin"> + <primary>pg_column_size</primary> + </indexterm> + <indexterm zone="functions-admin"> + <primary>pg_tablespace_size</primary> + </indexterm> + <indexterm zone="functions-admin"> + <primary>pg_database_size</primary> + </indexterm> + <indexterm zone="functions-admin"> + <primary>pg_relation_size</primary> + </indexterm> + <indexterm zone="functions-admin"> + <primary>pg_complete_relation_size</primary> + </indexterm> + <indexterm zone="functions-admin"> + <primary>pg_size_pretty</primary> + </indexterm> + <table id="functions-admin-dbsize"> <title>Database Object Size Functions</title> <tgroup cols="3"> @@ -9196,96 +9206,107 @@ SELECT set_config('log_statement_stats', 'off', false); <tbody> <row> + <entry><function>pg_column_size</function>(<parameter>any</parameter>)</entry> + <entry><type>integer</type></entry> + <entry>Number of bytes used to store a particular value (possibly compressed)</entry> + </row> + <row> <entry> <literal><function>pg_tablespace_size</function>(<parameter>oid</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the tablespace with the specified OID</entry> + <entry><type>bigint</type></entry> + <entry>Total disk space used by the tablespace with the specified OID</entry> </row> <row> <entry> <literal><function>pg_tablespace_size</function>(<parameter>name</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the tablespace with the specified name</entry> + <entry><type>bigint</type></entry> + <entry>Total disk space used by the tablespace with the specified name</entry> </row> <row> <entry> <literal><function>pg_database_size</function>(<parameter>oid</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the database with the specified OID</entry> + <entry><type>bigint</type></entry> + <entry>Total disk space used by the database with the specified OID</entry> </row> <row> <entry> <literal><function>pg_database_size</function>(<parameter>name</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the database with the specified name</entry> + <entry><type>bigint</type></entry> + <entry>Total disk space used by the database with the specified name</entry> </row> <row> <entry> <literal><function>pg_relation_size</function>(<parameter>oid</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the disk space used by the table or index with the specified OID</entry> + <entry><type>bigint</type></entry> + <entry>Disk space used by the table or index with the specified OID</entry> </row> <row> <entry> <literal><function>pg_relation_size</function>(<parameter>text</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the disk space used by the index or table with the specified name. - The name may be prefixed with a schema name if required</entry> + <entry><type>bigint</type></entry> + <entry>Disk space used by the table or index with the specified name. + The name may be qualified with a schema name</entry> </row> <row> <entry> <literal><function>pg_complete_relation_size</function>(<parameter>oid</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the table with the specified OID, + <entry><type>bigint</type></entry> + <entry>Total disk space used by the table with the specified OID, including indexes and toasted data</entry> </row> <row> <entry> <literal><function>pg_complete_relation_size</function>(<parameter>text</parameter>)</literal> </entry> - <entry><type>int8</type></entry> - <entry>Calculates the total disk space used by the table with the specified name, - including indexes and toasted data. The name may be prefixed with a schema name if - required</entry> + <entry><type>bigint</type></entry> + <entry>Total disk space used by the table with the specified name, + including indexes and toasted data. + The table name may be qualified with a schema name</entry> </row> <row> <entry> - <literal><function>pg_size_pretty</function>(<parameter>int8</parameter>)</literal> + <literal><function>pg_size_pretty</function>(<parameter>bigint</parameter>)</literal> </entry> <entry><type>text</type></entry> - <entry>Formats the size value (in bytes) into a human readable format with size units </entry> + <entry>Converts a size in bytes into a human-readable format with size units</entry> </row> </tbody> </tgroup> </table> <para> - <function>pg_tablespace_size</> and <function>pg_database_size</> accept an - oid or name of a tablespace or database, and return the disk space usage of the specified object. + <function>pg_column_size</> shows the space used to store any individual + data value. </para> - <indexterm zone="functions-admin"> - <primary>pg_relation_size</primary> - </indexterm> <para> - <function>pg_relation_size</> accepts the oid or name of a table, index or + <function>pg_tablespace_size</> and <function>pg_database_size</> accept + the OID or name of a tablespace or database, and return the total disk + space used therein. + </para> + + <para> + <function>pg_relation_size</> accepts the OID or name of a table, index or toast table, and returns the size in bytes. </para> + <para> - <function>pg_complete_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. + <function>pg_complete_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> - <function>pg_size_pretty</> can be used to format the size of the - database objects in a human readable way, using kB, MB, GB or TB as appropriate. + <function>pg_size_pretty</> can be used to format the result of one of + the other functions in a human-readable way, using kB, MB, GB or TB as + appropriate. </para> </sect1> |