<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 theobject exists, or

zero if theobject is a shared object, or

null if thelock object is on a transaction ID

OID of the database in which thelock target exists, or

zero if thetarget is a shared object, or

null if thetarget is a transaction ID

</entry>

</row>

<row>

<entry><structfield>relation</structfield></entry>

<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 thelock object is not

ona relation or part of a relation

OID of the relation targeted by the lock, or null if thetarget is not

a relation or part of a relation

</entry>

</row>

<row>

<entry><structfield>page</structfield></entry>

<entry><type>integer</type></entry>

<entry></entry>

<entry>

Page numberwithintherelation, or null ifthelock object

is not on a tuple orrelation page

Page numbertargeted bythelock withintherelation,

or null if the target is not arelation page or tuple

</entry>

</row>

<row>

<entry><structfield>tuple</structfield></entry>

<entry><type>smallint</type></entry>

<entry></entry>

<entry>

Tuple numberwithin the page, or null ifthe lockobject is not

on a tuple

Tuple numbertargeted bythe lockwithin the page,

or null if the target is not a tuple

</entry>

</row>

<row>

<entry><structfield>virtualxid</structfield></entry>

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

<entry></entry>

<entry>

Virtual ID ofa transactionlock, or null ifthe lock object is not

on a virtual transaction ID

Virtual ID ofthe transactiontargeted bythe lock,

or null if the target is not a virtual transaction ID

</entry>

</row>

<row>

<entry><structfield>transactionid</structfield></entry>

<entry><type>xid</type></entry>

<entry></entry>

<entry>

ID of a transaction lock, or null if the lock object is not on a transaction ID

ID of the transaction targeted by the lock,

or null if the target is not a transaction ID

</entry>

</row>

<row>

<entry><structfield>classid</structfield></entry>

<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 theobject, or null if the

lock objectis notona general database object.

OID of the system catalog containing thelock target, or null if the

targetis not a general database object

</entry>

</row>

<row>

<entry><structfield>objid</structfield></entry>

<entry><type>oid</type></entry>

<entry>any OID column</entry>

<entry>

OID of theobject within its system catalog, or null if the

lock objectis not on a general database object.

OID of thelock target within its system catalog, or null if the

targetis 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>

<entry><type>smallint</type></entry>

<entry></entry>

<entry>

For a table column, this isthecolumn number (the

Column number targeted bythelock (the

<structfield>classid</> and <structfield>objid</> refer to the

table itself). For all other object types, this column is

zero. Null if the lock object is not on a general database object.

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>