Consulta de Bloqueos en PostgreSql > 9.2 y como matar procesos

Para las versiones de Postgres 9.2 o superiores podéis crear una vista que facilitará la consulta de los procesos que actualmente tiene bloqueos en vuestro sistema:

CREATE OR REPLACE VIEW public.procesos_bloqueantes(
    blocking_pid,
    blocking_user,
    blocking_query,
    blocked_pid,
    blocked_user,
    blocked_query,
    age)
AS
  SELECT kl.pid AS blocking_pid,
         ka.usename AS blocking_user,
         ka.query AS blocking_query,
         bl.pid AS blocked_pid,
         a.usename AS blocked_user,
         a.query AS blocked_query,
         to_char(age(now(), a.query_start), 'HH24h:MIm:SSs' ::text) AS age
  FROM pg_locks bl
       JOIN pg_stat_activity a ON bl.pid = a.pid
       JOIN pg_locks kl ON bl.locktype = kl.locktype AND NOT bl.database IS
         DISTINCT
  FROM kl.database AND NOT bl.relation IS DISTINCT
  FROM kl.relation AND NOT bl.page IS DISTINCT
  FROM kl.page AND NOT bl.tuple IS DISTINCT
  FROM kl.tuple AND NOT bl.virtualxid IS DISTINCT
  FROM kl.virtualxid AND NOT bl.transactionid IS DISTINCT
  FROM kl.transactionid AND NOT bl.classid IS DISTINCT
  FROM kl.classid AND NOT bl.objid IS DISTINCT
  FROM kl.objid AND NOT bl.objsubid IS DISTINCT
  FROM kl.objsubid AND bl.pid <> kl.pid
       JOIN pg_stat_activity ka ON kl.pid = ka.pid
  WHERE kl.granted AND
        NOT bl.granted
  ORDER BY a.query_start;

Una vez localizados los procesos que están produciendo el bloqueo y que sentencia están ejecutando, podemos tomar la decisión de eliminarlos si llevan demasiado tiempo en ejecución y no nos importa perder él resultado de la acción que estaban ejecutando. El identificador de proceso a matar es el "blocking_id" de la vista:

select pg_cancel_backend ( blocking_pid );