PG sys function

PG(>=9.4) look archive status;

postgres=# select * from pg_stat_archiver;
-[ RECORD 1 ]------+------------------------------
archived_count | 10
last_archived_wal | 000000010000000000000009
last_archived_time | 2016-05-03 23:12:57.436303-07
failed_count | 0
last_failed_wal |
last_failed_time |
stats_reset | 2016-04-25 20:26:55.013401-07

PG sys function

原文：http://www.cnblogs.com/songyuejie/p/5458719.html