From 70a5fb49a74e2dfd57fa79ebbc0fc780ce898841 Mon Sep 17 00:00:00 2001
From: Varun Gupta <varun.gupta@mariadb.com>
Date: Thu, 16 May 2019 13:49:47 +0530
Subject: [PATCH] Fixed the case when statistics were not getting read because
 we had the statistics tables in the FROM list of the select. The statistics
 for tables are not read in such cases, so we need to check this case
 separately.

---
 mysql-test/r/stat_tables.result        | 11 +++++++++++
 mysql-test/r/stat_tables_innodb.result | 11 +++++++++++
 mysql-test/t/stat_tables.test          |  6 ++++++
 sql/opt_range.cc                       |  2 +-
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/mysql-test/r/stat_tables.result b/mysql-test/r/stat_tables.result
index afb3e12a474..d26221b5f8d 100644
--- a/mysql-test/r/stat_tables.result
+++ b/mysql-test/r/stat_tables.result
@@ -728,6 +728,17 @@ pk
 4
 3
 drop table t1,t2;
+create table t1(a int,b int, key k1(a) );
+insert into t1 values(1,1),(2,2),(3,3);
+analyze table t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	Engine-independent statistics collected
+test.t1	analyze	status	OK
+select * from mysql.index_stats, t1 where index_name='k1' and t1.a > 1 and t1.b > 1;
+db_name	table_name	index_name	prefix_arity	avg_frequency	a	b
+test	t1	k1	1	1.0000	2	2
+test	t1	k1	1	1.0000	3	3
+drop table t1;
 set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
 set @save_optimizer_switch=@@optimizer_switch;
 set use_stat_tables=@save_use_stat_tables;
diff --git a/mysql-test/r/stat_tables_innodb.result b/mysql-test/r/stat_tables_innodb.result
index 643a7aa55ea..b8bed681465 100644
--- a/mysql-test/r/stat_tables_innodb.result
+++ b/mysql-test/r/stat_tables_innodb.result
@@ -755,6 +755,17 @@ pk
 4
 3
 drop table t1,t2;
+create table t1(a int,b int, key k1(a) );
+insert into t1 values(1,1),(2,2),(3,3);
+analyze table t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	Engine-independent statistics collected
+test.t1	analyze	status	OK
+select * from mysql.index_stats, t1 where index_name='k1' and t1.a > 1 and t1.b > 1;
+db_name	table_name	index_name	prefix_arity	avg_frequency	a	b
+test	t1	k1	1	1.0000	2	2
+test	t1	k1	1	1.0000	3	3
+drop table t1;
 set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
 set @save_optimizer_switch=@@optimizer_switch;
 set use_stat_tables=@save_use_stat_tables;
diff --git a/mysql-test/t/stat_tables.test b/mysql-test/t/stat_tables.test
index 1e4d261c3f3..e9f37698a73 100644
--- a/mysql-test/t/stat_tables.test
+++ b/mysql-test/t/stat_tables.test
@@ -492,6 +492,12 @@ CREATE TABLE t2 SELECT pk FROM t1 WHERE pk>2;
 select * from t2;
 drop table t1,t2;
 
+create table t1(a int,b int, key k1(a) );
+insert into t1 values(1,1),(2,2),(3,3);
+analyze table t1;
+select * from mysql.index_stats, t1 where index_name='k1' and t1.a > 1 and t1.b > 1;
+drop table t1;
+
 set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
 
 set @save_optimizer_switch=@@optimizer_switch;
diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index 71e8055394c..e8421ad052a 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -3050,7 +3050,7 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item **cond)
 
   if (thd->variables.optimizer_use_condition_selectivity > 2 &&
       !bitmap_is_clear_all(used_fields) &&
-      thd->variables.use_stat_tables > 0)
+      thd->variables.use_stat_tables > 0 && table->stats_is_read)
   {
     PARAM param;
     MEM_ROOT alloc;