Document use of pg_locks.objid for advisory locks, suggestion from Marc Mamin

diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index de045d7057d2135b22a7c91f695943c33366e454..8a16c77a7ddb5c61ddfdd64880faaac32a645279 100644 (file)
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -1,4 +1,4 @@
-
+
 
@@ -5691,7 +5691,10 @@
       any OID column
       
        OID of the object within its system catalog, or NULL if the
-       object is not a general database object
+       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).
       
      
      

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 056d12a16886136d24bec8fcd0cbc3fc3acbaaf1..1052ab0d670ddde6f9d2b1cbc9cf6604aca5fafc 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1,4 +1,4 @@
-
+
 
  
   Functions and Operators
@@ -12378,7 +12378,8 @@ SELECT (pg_stat_file('filename')).modification;
    
     pg_advisory_lock locks an application-defined resource,
     which can be identified either by a single 64-bit key value or two
-    32-bit key values (note that these two key spaces do not overlap).  If
+    32-bit key values (note that these two key spaces do not overlap). 
+    The key type is specified in pg_locks.objid.  If
     another session already holds a lock on the same resource, the
     function will wait until the resource becomes available.  The lock
     is exclusive.  Multiple lock requests stack, so that if the same resource