diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/func.sgml | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 5c1cff3618d..34fea16eeee 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -14475,11 +14475,15 @@ SELECT set_config('log_statement_stats', 'off', false); <indexterm> <primary>pg_xlogfile_name_offset</primary> </indexterm> + <indexterm> + <primary>pg_xlog_location_diff</primary> + </indexterm> <para> The functions shown in <xref linkend="functions-admin-backup-table"> assist in making on-line backups. - These functions cannot be executed during recovery. + These functions cannot be executed during recovery (except + <function>pg_xlog_location_diff</function>). </para> <table id="functions-admin-backup-table"> @@ -14547,6 +14551,13 @@ SELECT set_config('log_statement_stats', 'off', false); <entry><type>text</>, <type>integer</></entry> <entry>Convert transaction log location string to file name and decimal byte offset within file</entry> </row> + <row> + <entry> + <literal><function>pg_xlog_location_diff(<parameter>location</> <type>text</>, <parameter>location</> <type>text</>)</function></literal> + </entry> + <entry><type>numeric</></entry> + <entry>Calculate the difference between two transaction log locations</entry> + </row> </tbody> </tgroup> </table> @@ -14640,6 +14651,13 @@ postgres=# SELECT * FROM pg_xlogfile_name_offset(pg_stop_backup()); </para> <para> + <function>pg_xlog_location_diff</> calculates the difference in bytes + between two transaction log locations. It can be used with + <structname>pg_stat_replication</structname> or some functions shown in + <xref linkend="functions-admin-backup-table"> to get the replication lag. + </para> + + <para> For details about proper usage of these functions, see <xref linkend="continuous-archiving">. </para> |