lib/postgres/vacuum/monitor/query.rb in postgres-vacuum-monitor-0.7.0 vs lib/postgres/vacuum/monitor/query.rb in postgres-vacuum-monitor-0.8.0

@@ -65,9 +65,39 @@
                     AND ( age(relfrozenxid) >= coalesce(cfma.value::float, autovacuum_freeze_max_age::float)
                     OR coalesce(cvbt.value::float, autovacuum_vacuum_threshold::float) + coalesce(cvsf.value::float,autovacuum_vacuum_scale_factor::float) * pg_table_size(c.oid) <= n_dead_tup)
             ORDER BY  age(relfrozenxid) DESC LIMIT 50;
           SQL
         end
+
+        def blocked_queries
+          # The query was taken from https://wiki.postgresql.org/wiki/Lock_Monitoring
+          <<-SQL
+            SELECT blocked_locks.pid AS blocked_pid,
+              blocked_activity.usename AS blocked_user,
+              blocking_locks.pid AS blocking_pid,
+              blocking_activity.usename AS blocking_user,
+              blocked_activity.query AS blocked_statement,
+              blocking_activity.query AS current_statement_in_blocking_process,
+              blocked_activity.application_name AS blocked_application,
+              blocking_activity.application_name AS blocking_application
+            FROM pg_catalog.pg_locks blocked_locks
+            JOIN pg_catalog.pg_stat_activity blocked_activity  ON blocked_activity.pid = blocked_locks.pid
+            JOIN pg_catalog.pg_locks blocking_locks 
+              ON blocking_locks.locktype = blocked_locks.locktype
+              AND blocking_locks.DATABASE IS NOT DISTINCT FROM blocked_locks.DATABASE
+              AND blocking_locks.relation IS NOT DISTINCT FROM blocked_locks.relation
+              AND blocking_locks.page IS NOT DISTINCT FROM blocked_locks.page
+              AND blocking_locks.tuple IS NOT DISTINCT FROM blocked_locks.tuple
+              AND blocking_locks.virtualxid IS NOT DISTINCT FROM blocked_locks.virtualxid
+              AND blocking_locks.transactionid IS NOT DISTINCT FROM blocked_locks.transactionid
+              AND blocking_locks.classid IS NOT DISTINCT FROM blocked_locks.classid
+              AND blocking_locks.objid IS NOT DISTINCT FROM blocked_locks.objid
+              AND blocking_locks.objsubid IS NOT DISTINCT FROM blocked_locks.objsubid
+              AND blocking_locks.pid != blocked_locks.pid
+            JOIN pg_catalog.pg_stat_activity blocking_activity ON blocking_activity.pid = blocking_locks.pid
+            WHERE NOT blocked_locks.GRANTED;
+          SQL
+        end
       end
     end
   end
 end