diff options
| -rw-r--r-- | doc/src/sgml/catalogs.sgml | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index d115589c53c..303f3a6f921 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -7092,16 +7092,27 @@ <para> The <structfield>pid</structfield> column can be joined to the - <structfield>procpid</structfield> column of the - <structname>pg_stat_activity</structname> view to get more - information on the session holding or waiting to hold each lock. + <structfield>procpid</structfield> column of the <link + linkend="monitoring-stats-views"><structname>pg_stat_activity</structname></link> + view to get more + information on the session holding or waiting to hold each lock, + for example +<programlisting> +SELECT * FROM pg_locks pl LEFT JOIN pg_stat_activity psa + ON pl.pid = psa.procpid; +</programlisting> Also, if you are using prepared transactions, the - <structfield>transaction</> column can be joined to the - <structfield>transaction</structfield> column of the - <structname>pg_prepared_xacts</structname> view to get more - information on prepared transactions that hold locks. + <structfield>virtualtransaction</> column can be joined to the + <structfield>transaction</structfield> column of the <link + linkend="view-pg-prepared-xacts"><structname>pg_prepared_xacts</structname></link> + view to get more information on prepared transactions that hold locks. (A prepared transaction can never be waiting for a lock, but it continues to hold the locks it acquired while running.) + For example: +<programlisting> +SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx + ON pl.virtualtransaction = '-1/' || ppx.transaction; +</programlisting> </para> <para> |