MDEV-4981: Account for queries handled by query-cache in USER_STATISTICS (and in HOST_STATISTICS)

Added collection statistics for queries resolved via query cache.

mysql-test/r/query_cache.result

@@ -1932,6 +1932,85 @@ set local query_cache_type= on;
 select @@query_cache_size, @@global.query_cache_type, @@local.query_cache_type;
 @@query_cache_size	@@global.query_cache_type	@@local.query_cache_type
 20971520	ON	ON
+#
+# MDEV-4981: Account for queries handled by query-cache in
+# USER_STATISTICS (and in HOST_STATISTICS)
+#
+SET GLOBAL userstat=1;
+set GLOBAL query_cache_size=1355776;
+FLUSH USER_STATISTICS;
+FLUSH CLIENT_STATISTICS;
+reset query cache;
+flush status;
+create table t1 (a int);
+insert into t1 values (1);
+select * from t1;
+a
+1
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+1	1	0
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+2	2	0
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	0
+select * from t1;
+a
+1
+select * from t1;
+a
+1
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+5	5	0
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+6	6	0
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	2
+drop table t1;
+FLUSH USER_STATISTICS;
+FLUSH CLIENT_STATISTICS;
+flush status;
+create table t1 (a int);
+select * from t1;
+a
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+1	0	1
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+2	1	1
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	0
+select * from t1;
+a
+select * from t1;
+a
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+5	2	3
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+SELECT_COMMANDS	ROWS_SENT	EMPTY_QUERIES
+6	3	3
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	2
+drop table t1;
+SET GLOBAL userstat=default;
+End of 5.5 tests
 restore defaults
 SET GLOBAL query_cache_type= default;
 SET GLOBAL query_cache_size= default;

mysql-test/t/query_cache.test

@@ -1617,6 +1617,58 @@ select @@query_cache_size, @@global.query_cache_type, @@local.query_cache_type;
 set local query_cache_type= on;
 select @@query_cache_size, @@global.query_cache_type, @@local.query_cache_type;
 
+--echo #
+--echo # MDEV-4981: Account for queries handled by query-cache in
+--echo # USER_STATISTICS (and in HOST_STATISTICS)
+--echo #
+
+SET GLOBAL userstat=1;
+set GLOBAL query_cache_size=1355776;
+FLUSH USER_STATISTICS;
+FLUSH CLIENT_STATISTICS;
+reset query cache;
+flush status;
+
+create table t1 (a int);
+insert into t1 values (1);
+select * from t1;
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+show status like "Qcache_hits";
+select * from t1;
+select * from t1;
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+show status like "Qcache_hits";
+
+drop table t1;
+FLUSH USER_STATISTICS;
+FLUSH CLIENT_STATISTICS;
+flush status;
+
+create table t1 (a int);
+select * from t1;
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+show status like "Qcache_hits";
+select * from t1;
+select * from t1;
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.CLIENT_STATISTICS
+where CLIENT="localhost";
+select SELECT_COMMANDS,ROWS_SENT,EMPTY_QUERIES from INFORMATION_SCHEMA.USER_STATISTICS
+where USER="root";
+show status like "Qcache_hits";
+
+drop table t1;
+SET GLOBAL userstat=default;
+
+--echo End of 5.5 tests
 
 --echo restore defaults
 SET GLOBAL query_cache_type= default;

sql/sql_cache.cc

@@ -2074,9 +2074,13 @@ def_week_frmt: %lu, in_trans: %d, autocommit: %d",
   }
 #endif /*!EMBEDDED_LIBRARY*/
 
-  thd->limit_found_rows = query->found_rows();
+  thd->sent_row_count= thd->limit_found_rows = query->found_rows();
   thd->status_var.last_query_cost= 0.0;
   thd->query_plan_flags= (thd->query_plan_flags & ~QPLAN_QC_NO) | QPLAN_QC;
+  if (!thd->sent_row_count)
+    status_var_increment(thd->status_var.empty_queries);
+  else
+    status_var_add(thd->status_var.rows_sent, thd->sent_row_count);
 
   /*
     End the statement transaction potentially started by an

sql/sql_parse.cc

@@ -4656,7 +4656,8 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables)
   /* Count number of empty select queries */
   if (!thd->sent_row_count)
     status_var_increment(thd->status_var.empty_queries);
-  status_var_add(thd->status_var.rows_sent, thd->sent_row_count);
+  else
+    status_var_add(thd->status_var.rows_sent, thd->sent_row_count);
   return res;
 }
 
@@ -5790,6 +5791,8 @@ void mysql_parse(THD *thd, char *rawbuf, uint length,
   {
     /* Update statistics for getting the query from the cache */
     thd->lex->sql_command= SQLCOM_SELECT;
+    status_var_increment(thd->status_var.com_stat[thd->lex->sql_command]);
+    thd->update_stats();
   }
   DBUG_VOID_RETURN;
 }