Merge 10.4 into 10.5

8 files changed, 141 insertions, 14 deletions

diff --git a/mysql-test/main/derived_cond_pushdown.result b/mysql-test/main/derived_cond_pushdown.result
index 33b625a0f6d..016ca22af1b 100644
--- a/mysql-test/main/derived_cond_pushdown.result
+++ b/mysql-test/main/derived_cond_pushdown.result
@@ -16679,7 +16679,7 @@ EXPLAIN EXTENDED
 SELECT * FROM v1 JOIN v2 ON v1.f = v2.f;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
-3	LATERAL DERIVED	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
+3	DERIVED	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 Warnings:
 Note	1003	/* select#1 */ select NULL AS `f`,`v2`.`f` AS `f` from `test`.`t1` `a` straight_join `test`.`t1` `b` join `test`.`v2` where 0
 DROP VIEW v1,v2;
diff --git a/mysql-test/main/derived_split_innodb.result b/mysql-test/main/derived_split_innodb.result
index 55ace91507e..9edf9a1f2ae 100644
--- a/mysql-test/main/derived_split_innodb.result
+++ b/mysql-test/main/derived_split_innodb.result
@@ -176,3 +176,68 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 3	LATERAL DERIVED	t1	ref	a,a_2	a	5	test.t1.a	1	Using where; Using temporary; Using filesort
 3	LATERAL DERIVED	t2	ref	c	c	5	test.t1.b	1	Using index
 DROP TABLE t1, t2;
+#
+# Bug mdev-25714: usage non-splitting covering index is cheaper than
+#                 usage of the best splitting index for one group
+#
+create table t1 (
+id int not null, itemid int not null, index idx (itemid)
+) engine=innodb;
+insert into t1 values (1, 2), (2,2), (4,2), (4,2), (0,3), (3,3);
+create table t2 (id int not null) engine=innodb;
+insert into t2 values (2);
+create table t3 (
+id int not null, itemid int not null, userid int not null, primary key (id),
+index idx1 (userid, itemid), index idx2 (itemid)
+) engine innodb;
+insert into t3 values (1,1,1), (2,1,1), (3,2,1), (4,2,1), (5,3,1);
+set use_stat_tables='never';
+set optimizer_use_condition_selectivity=1;
+analyze table t1,t2,t3;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+test.t2	analyze	status	OK
+test.t3	analyze	status	OK
+set optimizer_switch='split_materialized=on';
+explain select t1.id, t1.itemid, dt.id, t2.id
+from t1,
+(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
+t2
+where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	<derived2>	ref	key1	key1	4	test.t2.id	2	
+1	PRIMARY	t1	ALL	idx	NULL	NULL	NULL	6	Using where; Using join buffer (flat, BNL join)
+2	DERIVED	t3	ref	idx1,idx2	idx1	4	const	5	Using where; Using index
+select t1.id, t1.itemid, dt.id, t2.id
+from t1,
+(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
+t2
+where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
+id	itemid	id	id
+4	2	4	2
+4	2	4	2
+set optimizer_switch='split_materialized=off';
+explain select t1.id, t1.itemid, dt.id, t2.id
+from t1,
+(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
+t2
+where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	<derived2>	ref	key1	key1	4	test.t2.id	2	
+1	PRIMARY	t1	ALL	idx	NULL	NULL	NULL	6	Using where; Using join buffer (flat, BNL join)
+2	DERIVED	t3	ref	idx1	idx1	4	const	5	Using where; Using index
+select t1.id, t1.itemid, dt.id, t2.id
+from t1,
+(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
+t2
+where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
+id	itemid	id	id
+4	2	4	2
+4	2	4	2
+drop table t1,t2,t3;
+set optimizer_switch='split_materialized=default';
+set use_stat_tables=default;
+set optimizer_use_condition_selectivity=default;
+# End of 10.3 tests
diff --git a/mysql-test/main/derived_split_innodb.test b/mysql-test/main/derived_split_innodb.test
index 10fc3f93190..bee9ef497b6 100644
--- a/mysql-test/main/derived_split_innodb.test
+++ b/mysql-test/main/derived_split_innodb.test
@@ -152,3 +152,44 @@ eval set statement optimizer_switch='split_materialized=on' for  $query;
 
 DROP TABLE t1, t2;
 
+--echo #
+--echo # Bug mdev-25714: usage non-splitting covering index is cheaper than
+--echo #                 usage of the best splitting index for one group
+--echo #
+
+create table t1 (
+  id int not null, itemid int not null, index idx (itemid)
+) engine=innodb;
+insert into t1 values (1, 2), (2,2), (4,2), (4,2), (0,3), (3,3);
+create table t2 (id int not null) engine=innodb;
+insert into t2 values (2);
+create table t3 (
+  id int not null, itemid int not null, userid int not null, primary key (id),
+  index idx1 (userid, itemid), index idx2 (itemid)
+) engine innodb;
+insert into t3 values (1,1,1), (2,1,1), (3,2,1), (4,2,1), (5,3,1);
+set use_stat_tables='never';
+set optimizer_use_condition_selectivity=1;
+analyze table t1,t2,t3;
+
+let $q=
+select t1.id, t1.itemid, dt.id, t2.id
+  from t1,
+  (select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
+  t2
+    where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
+
+set optimizer_switch='split_materialized=on';
+eval explain $q;
+eval $q;
+
+set optimizer_switch='split_materialized=off';
+eval explain $q;
+eval $q;
+
+drop table t1,t2,t3;
+set optimizer_switch='split_materialized=default';
+set use_stat_tables=default;
+set optimizer_use_condition_selectivity=default;
+
+--echo # End of 10.3 tests
diff --git a/mysql-test/main/lock_kill.test b/mysql-test/main/lock_kill.test
index dfeebbc4f6a..2c1396e5ff3 100644
--- a/mysql-test/main/lock_kill.test
+++ b/mysql-test/main/lock_kill.test
@@ -17,7 +17,7 @@ LOCK TABLE t1 WRITE;
 eval KILL $conid;
 --enable_query_log
 --connection con1
---error 0,2013,ER_CONNECTION_KILLED
+--error 0,2006,2013,ER_CONNECTION_KILLED
 reap;
 --connection default
 --disconnect con1
@@ -35,7 +35,7 @@ LOCK TABLE t1 WRITE, t2 WRITE;
 eval KILL $conid;
 --enable_query_log
 --connection con1
---error 0,2013,ER_CONNECTION_KILLED
+--error 0,2006,2013,ER_CONNECTION_KILLED
 reap;
 --connection default
 --disconnect con1
diff --git a/sql/field.cc b/sql/field.cc
index f3deffccee5..ab4f6a96921 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -7857,7 +7857,7 @@ bool Field_varstring::send(Protocol *protocol)
 #ifdef HAVE_MEM_CHECK
 void Field_varstring::mark_unused_memory_as_defined()
 {
-  uint used_length= get_length();
+  uint used_length __attribute__((unused)) = get_length();
   MEM_MAKE_DEFINED(get_data() + used_length, field_length - used_length);
 }
 #endif
diff --git a/sql/opt_split.cc b/sql/opt_split.cc
index 28a54838169..316919c4a81 100644
--- a/sql/opt_split.cc
+++ b/sql/opt_split.cc
@@ -958,11 +958,7 @@ SplM_plan_info * JOIN_TAB::choose_best_splitting(double record_count,
       in the cache
     */
     spl_plan= spl_opt_info->find_plan(best_table, best_key, best_key_parts);
-    if (!spl_plan &&
-	(spl_plan= (SplM_plan_info *) thd->alloc(sizeof(SplM_plan_info))) &&
-	(spl_plan->best_positions=
-	   (POSITION *) thd->alloc(sizeof(POSITION) * join->table_count)) &&
-	!spl_opt_info->plan_cache.push_back(spl_plan))
+    if (!spl_plan)
     {
       /*
         The plan for the chosen key has not been found in the cache.
@@ -972,6 +968,27 @@ SplM_plan_info * JOIN_TAB::choose_best_splitting(double record_count,
       reset_validity_vars_for_keyuses(best_key_keyuse_ext_start, best_table,
                                       best_key, remaining_tables, true);
       choose_plan(join, all_table_map & ~join->const_table_map);
+
+      /*
+        Check that the chosen plan is really a splitting plan.
+        If not or if there is not enough memory to save the plan in the cache
+        then just return with no splitting plan.
+      */
+      POSITION *first_non_const_pos= join->best_positions + join->const_tables;
+      TABLE *table= first_non_const_pos->table->table;
+      key_map spl_keys= table->keys_usable_for_splitting;
+      if (!(first_non_const_pos->key &&
+            spl_keys.is_set(first_non_const_pos->key->key)) ||
+          !(spl_plan= (SplM_plan_info *) thd->alloc(sizeof(SplM_plan_info))) ||
+	  !(spl_plan->best_positions=
+	     (POSITION *) thd->alloc(sizeof(POSITION) * join->table_count)) ||
+	  spl_opt_info->plan_cache.push_back(spl_plan))
+      {
+        reset_validity_vars_for_keyuses(best_key_keyuse_ext_start, best_table,
+                                        best_key, remaining_tables, false);
+        return 0;
+      }
+
       spl_plan->keyuse_ext_start= best_key_keyuse_ext_start;
       spl_plan->table= best_table;
       spl_plan->key= best_key;
diff --git a/storage/innobase/include/srv0mon.h b/storage/innobase/include/srv0mon.h
index 77a90b0c84a..cbda9d06338 100644
--- a/storage/innobase/include/srv0mon.h
+++ b/storage/innobase/include/srv0mon.h
@@ -639,7 +639,7 @@ Use MONITOR_DEC if appropriate mutex protection exists.
 
 #ifdef HAVE_MEM_CHECK
 # define MONITOR_CHECK_DEFINED(value) do {	\
-	mon_type_t m = value;			\
+    mon_type_t m __attribute__((unused))= value;        \
 	MEM_CHECK_DEFINED(&m, sizeof m);	\
 } while (0)
 #else /* HAVE_MEM_CHECK */
diff --git a/storage/innobase/page/page0cur.cc b/storage/innobase/page/page0cur.cc
index f75d1a8be77..cc6b1797d61 100644
--- a/storage/innobase/page/page0cur.cc
+++ b/storage/innobase/page/page0cur.cc
@@ -1315,8 +1315,10 @@ page_cur_insert_rec_low(
 
 #ifdef HAVE_MEM_CHECK
   {
-    const void *rec_start= rec - rec_offs_extra_size(offsets);
-    ulint extra_size= rec_offs_extra_size(offsets) -
+    const void *rec_start __attribute__((unused))=
+      rec - rec_offs_extra_size(offsets);
+    ulint extra_size __attribute__((unused))=
+      rec_offs_extra_size(offsets) -
       (page_is_comp(block->frame)
        ? REC_N_NEW_EXTRA_BYTES
        : REC_N_OLD_EXTRA_BYTES);
@@ -1722,8 +1724,10 @@ page_cur_insert_rec_zip(
 
 #ifdef HAVE_MEM_CHECK
   {
-    const void *rec_start= rec - rec_offs_extra_size(offsets);
-    ulint extra_size= rec_offs_extra_size(offsets) - REC_N_NEW_EXTRA_BYTES;
+    const void *rec_start __attribute__((unused))=
+      rec - rec_offs_extra_size(offsets);
+    ulint extra_size __attribute__((unused))=
+      rec_offs_extra_size(offsets) - REC_N_NEW_EXTRA_BYTES;
     /* All data bytes of the record must be valid. */
     MEM_CHECK_DEFINED(rec, rec_offs_data_size(offsets));
     /* The variable-length header must be valid. */