Re: Need help understanding pg_locks

On Jul14, 2011, at 22:18 , Bruce Momjian wrote:
> !        OID of the database in which the lock target exists, or
> !        zero if the lock is a shared object, or
> !        null if the lock is on a transaction ID

For consistency, I think it should say "target" in the second part
of the sentence also now, instead of "lock ... on".

Updated patch attached. I tried to make the descriptions a
bit more consistent, replaced "object" by "target", and
added "targeted by" after the phrase which describes the
locked (or waited-for) object.

best regards,
Florian Pflug

diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index d4a1d36..33be5d0 100644
*** a/doc/src/sgml/catalogs.sgml
--- b/doc/src/sgml/catalogs.sgml
***************
*** 6928,6936 ****       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-database"><structname>pg_database</structname></link>.oid</literal></entry>      <entry> 
!        OID of the database in which the object exists, or
!        zero if the object is a shared object, or
!        null if the object is a transaction ID       </entry>      </row>      <row>
--- 6928,6936 ----       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-database"><structname>pg_database</structname></link>.oid</literal></entry>      <entry> 
!        OID of the database in which the lock target exists, or
!        zero if the target is a shared object, or
!        null if the target is a transaction ID       </entry>      </row>      <row>
***************
*** 6938,6944 ****       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-class"><structname>pg_class</structname></link>.oid</literal></entry>      <entry> 
!        OID of the relation, or null if the object is not        a relation or part of a relation       </entry>
</row>
--- 6938,6944 ----       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-class"><structname>pg_class</structname></link>.oid</literal></entry>      <entry> 
!        OID of the relation targeted by the lock, or null if the target is not        a relation or part of a relation
     </entry>      </row> 
***************
*** 6947,6954 ****       <entry><type>integer</type></entry>       <entry></entry>       <entry>
!        Page number within the relation, or null if the object
!        is not a tuple or relation page       </entry>      </row>      <row>
--- 6947,6954 ----       <entry><type>integer</type></entry>       <entry></entry>       <entry>
!        Page number targeted by the lock within the relation,
!        or null if the target is not a relation page or tuple       </entry>      </row>      <row>
***************
*** 6956,6962 ****       <entry><type>smallint</type></entry>       <entry></entry>       <entry>
!        Tuple number within the page, or null if the object is not a tuple       </entry>      </row>      <row>
--- 6956,6963 ----       <entry><type>smallint</type></entry>       <entry></entry>       <entry>
!        Tuple number targeted by the lock within the page,
!        or null if the target is not a tuple       </entry>      </row>      <row>
***************
*** 6964,6971 ****       <entry><type>text</type></entry>       <entry></entry>       <entry>
!        Virtual ID of a transaction, or null if the object is not a
!        virtual transaction ID       </entry>      </row>      <row>
--- 6965,6972 ----       <entry><type>text</type></entry>       <entry></entry>       <entry>
!        Virtual ID of the transaction targeted by the lock,
!        or null if the target is not a virtual transaction ID       </entry>      </row>      <row>
***************
*** 6973,6979 ****       <entry><type>xid</type></entry>       <entry></entry>       <entry>
!        ID of a transaction, or null if the object is not a transaction ID       </entry>      </row>      <row>
--- 6974,6981 ----       <entry><type>xid</type></entry>       <entry></entry>       <entry>
!        ID of the transaction targeted by the lock,
!        or null if the target is not a transaction ID       </entry>      </row>      <row>
***************
*** 6981,6988 ****       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-class"><structname>pg_class</structname></link>.oid</literal></entry>      <entry> 
!        OID of the system catalog containing the object, or null if the
!        object is not a general database object       </entry>      </row>      <row>
--- 6983,6990 ----       <entry><type>oid</type></entry>       <entry><literal><link
linkend="catalog-pg-class"><structname>pg_class</structname></link>.oid</literal></entry>      <entry> 
!        OID of the system catalog containing the lock target, or null if the
!        target is not a general database object       </entry>      </row>      <row>
***************
*** 6990,6997 ****       <entry><type>oid</type></entry>       <entry>any OID column</entry>       <entry>
!        OID of the object within its system catalog, or null if the
!        object is not a general database object.        For advisory locks it is used to distinguish the two key
spaces (1 for an int8 key, 2 for two int4 keys).       </entry> 
--- 6992,6999 ----       <entry><type>oid</type></entry>       <entry>any OID column</entry>       <entry>
!        OID of the lock target within its system catalog, or null if the
!        target is not a general database object.        For advisory locks it is used to distinguish the two key
spaces (1 for an int8 key, 2 for two int4 keys).       </entry> 
***************
*** 7001,7010 ****       <entry><type>smallint</type></entry>       <entry></entry>       <entry>
!        For a table column, this is the column number (the        <structfield>classid</> and <structfield>objid</>
referto the 
!        table itself).  For all other object types, this column is
!        zero.  Null if the object is not a general database object       </entry>      </row>      <row>
--- 7003,7013 ----       <entry><type>smallint</type></entry>       <entry></entry>       <entry>
!        Column number targeted by the lock (the        <structfield>classid</> and <structfield>objid</> refer to the
!        table itself),
!        or zero if the target is some other general database object,
!        or null if the target is not a general database object       </entry>      </row>      <row>