Separate state from query string in pg_stat_activity

This separates the state (running/idle/idleintransaction etc) into
it's own field ("state"), and leaves the query field containing just
query text.

The query text will now mean "current query" when a query is running
and "last query" in other states. Accordingly,the field has been
renamed from current_query to query.

Since backwards compatibility was broken anyway to make that, the procpid
field has also been renamed to pid - along with the same field in
pg_stat_replication for consistency.

Scott Mead and Magnus Hagander, review work from Greg Smith

1 files changed, 20 insertions, 1 deletions

diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index b8c6d82d0ea..fa52447048d 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -589,10 +589,25 @@ typedef struct PgStat_GlobalStats
 
 
 /* ----------
+ * Backend states
+ * ----------
+ */
+typedef enum BackendState {
+	STATE_UNDEFINED,
+	STATE_IDLE,
+	STATE_RUNNING,
+	STATE_IDLEINTRANSACTION,
+	STATE_FASTPATH,
+	STATE_IDLEINTRANSACTION_ABORTED,
+	STATE_DISABLED,
+} BackendState;
+
+/* ----------
  * Shared-memory data structures
  * ----------
  */
 
+
 /* ----------
  * PgBackendStatus
  *
@@ -622,6 +637,7 @@ typedef struct PgBackendStatus
 	TimestampTz st_proc_start_timestamp;
 	TimestampTz st_xact_start_timestamp;
 	TimestampTz st_activity_start_timestamp;
+    TimestampTz st_state_start_timestamp;
 
 	/* Database OID, owning user's OID, connection client address */
 	Oid			st_databaseid;
@@ -632,6 +648,9 @@ typedef struct PgBackendStatus
 	/* Is backend currently waiting on an lmgr lock? */
 	bool		st_waiting;
 
+    /* current state */
+    BackendState	st_state;
+
 	/* application name; MUST be null-terminated */
 	char	   *st_appname;
 
@@ -715,7 +734,7 @@ extern void pgstat_report_recovery_conflict(int reason);
 extern void pgstat_initialize(void);
 extern void pgstat_bestart(void);
 
-extern void pgstat_report_activity(const char *cmd_str);
+extern void pgstat_report_activity(BackendState state, const char *cmd_str);
 extern void pgstat_report_appname(const char *appname);
 extern void pgstat_report_xact_timestamp(TimestampTz tstamp);
 extern void pgstat_report_waiting(bool waiting);