Merge branch '10.8' into 10.9

mysql-test/main/selectivity_no_engine.result

@@ -314,6 +314,29 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	a	ALL	NULL	NULL	NULL	NULL	5	Using where
 1	SIMPLE	b	hash_ALL	NULL	#hash#$hj	1341	test.a.Host,test.a.User,test.a.Password,test.a.Select_priv,test.a.Insert_priv,test.a.Update_priv,test.a.Delete_priv,test.a.Create_priv,test.a.Drop_priv,test.a.Reload_priv,test.a.Shutdown_priv,test.a.Process_priv,test.a.File_priv,test.a.Grant_priv,test.a.References_priv,test.a.Index_priv,test.a.Alter_priv,test.a.Show_db_priv,test.a.Super_priv,test.a.Create_tmp_table_priv,test.a.Lock_tables_priv,test.a.Execute_priv,test.a.Repl_slave_priv,test.a.Repl_client_priv,test.a.Create_view_priv,test.a.Show_view_priv,test.a.Create_routine_priv,test.a.Alter_routine_priv,test.a.Create_user_priv,test.a.Event_priv,test.a.Trigger_priv,test.a.Create_tablespace_priv,test.a.Delete_history_priv,test.a.ssl_type,test.a.ssl_cipher,test.a.x509_issuer,test.a.x509_subject,test.a.max_questions,test.a.max_updates,test.a.max_connections,test.a.max_user_connections,test.a.plugin,test.a.authentication_string,test.a.password_expired,test.a.is_role,test.a.default_role,test.a.max_statement_time	5	Using where; Using join buffer (flat, BNLH join)
 DROP TABLE t1,t2,t3;
+#
+# MDEV-31199: Assertion `field->table->stats_is_read' fails with hash_join_cardinality=on
+#
+CREATE TABLE t1 (a VARCHAR(255));
+INSERT INTO t1 VALUES ('u'),('uu');
+CREATE TABLE t2 (b VARCHAR(255)) CHARACTER SET utf8mb4;
+INSERT INTO t2 VALUES ('x'),('xx');
+CREATE TABLE t3 (c VARCHAR(255));
+INSERT INTO t3 VALUES ('z'),('zz');
+ANALYZE TABLE t1, t2, t3 PERSISTENT FOR ALL;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	Engine-independent statistics collected
+test.t1	analyze	status	OK
+test.t2	analyze	status	Engine-independent statistics collected
+test.t2	analyze	status	OK
+test.t3	analyze	status	Engine-independent statistics collected
+test.t3	analyze	status	OK
+set @tmp1=@@optimizer_switch, @tmp2=@@join_cache_level;
+set optimizer_switch='hash_join_cardinality=on', join_cache_level=3;
+SELECT t1.* FROM t1 JOIN (SELECT DISTINCT b FROM t2 JOIN t3) sq ON sq.b = t1.a;
+a
+set optimizer_switch=@tmp1, join_cache_level=@tmp2;
+DROP TABLE t1, t2, t3;
 # 
 # End of the test file
 # 

mysql-test/main/selectivity_no_engine.test

@@ -250,6 +250,26 @@ SELECT * FROM t1 AS a NATURAL JOIN t1 AS b;
 
 DROP TABLE t1,t2,t3;
 
+--echo #
+--echo # MDEV-31199: Assertion `field->table->stats_is_read' fails with hash_join_cardinality=on
+--echo #
+CREATE TABLE t1 (a VARCHAR(255));
+INSERT INTO t1 VALUES ('u'),('uu');
+
+CREATE TABLE t2 (b VARCHAR(255)) CHARACTER SET utf8mb4;
+INSERT INTO t2 VALUES ('x'),('xx');
+
+CREATE TABLE t3 (c VARCHAR(255));
+INSERT INTO t3 VALUES ('z'),('zz');
+
+ANALYZE TABLE t1, t2, t3 PERSISTENT FOR ALL; # Optional, fails either way
+
+set @tmp1=@@optimizer_switch, @tmp2=@@join_cache_level;
+set optimizer_switch='hash_join_cardinality=on', join_cache_level=3;
+SELECT t1.* FROM t1 JOIN (SELECT DISTINCT b FROM t2 JOIN t3) sq ON sq.b = t1.a;
+set optimizer_switch=@tmp1, join_cache_level=@tmp2;
+DROP TABLE t1, t2, t3;
+
 --echo # 
 --echo # End of the test file
 --echo # 

sql/field.cc

@@ -2557,6 +2557,7 @@ Field *Field::make_new_field(MEM_ROOT *root, TABLE *new_table,
   tmp->key_start.init(0);
   tmp->part_of_key.init(0);
   tmp->part_of_sortkey.init(0);
+  tmp->read_stats= NULL;
   /*
     TODO: it is not clear why this method needs to reset unireg_check.
     Try not to reset it, or explain why it needs to be reset.