MDEV-30310 Assertion failure in best_access_path upon IN exceeding IN_PREDICATE_CONVERSION_THRESHOLD, derived_with_keys=off

The bug was some old code that, without any explanation, reset
PART_KEY_FLAG from fields in temporary tables. This caused
join_tab->key_dependent to not be updated properly, which caused
an assert.

8 files changed, 46 insertions, 13 deletions

diff --git a/mysql-test/main/derived.result b/mysql-test/main/derived.result
index 0eb4f131571..91e85ef4339 100644
--- a/mysql-test/main/derived.result
+++ b/mysql-test/main/derived.result
@@ -1419,5 +1419,24 @@ A
 1
 drop table t1, duplicates_tbl;
 #
+# MDEV-30310
+# Assertion failure in best_access_path upon IN exceeding
+# IN_PREDICATE_CONVERSION_THRESHOLD, derived_with_keys=off
+#
+CREATE TABLE t1 (l_orderkey int);
+INSERT INTO t1 VALUES (1),(2);
+CREATE TABLE t2 (o_orderkey int);
+INSERT INTO t2 VALUES (3),(4);
+SET IN_PREDICATE_CONVERSION_THRESHOLD= 2;
+SET OPTIMIZER_SWITCH='derived_with_keys=on';
+SELECT * FROM t1 JOIN t2 ON (l_orderkey = o_orderkey) WHERE l_orderkey IN (1, 2, 3);
+l_orderkey	o_orderkey
+SET OPTIMIZER_SWITCH='derived_with_keys=off';
+SELECT * FROM t1 JOIN t2 ON (l_orderkey = o_orderkey) WHERE l_orderkey IN (1, 2, 3);
+l_orderkey	o_orderkey
+SET @@IN_PREDICATE_CONVERSION_THRESHOLD=@@global.IN_PREDICATE_CONVERSION_THRESHOLD;
+SET @@OPTIMIZER_SWITCH=@@global.OPTIMIZER_SWITCH;
+DROP TABLE t1, t2;
+#
 # End of 11.0 tests
 #
diff --git a/mysql-test/main/derived.test b/mysql-test/main/derived.test
index 3bb52e603f9..5119bca4ea8 100644
--- a/mysql-test/main/derived.test
+++ b/mysql-test/main/derived.test
@@ -1206,5 +1206,24 @@ from t1;
 drop table t1, duplicates_tbl;
 
 --echo #
+--echo # MDEV-30310
+--echo # Assertion failure in best_access_path upon IN exceeding
+--echo # IN_PREDICATE_CONVERSION_THRESHOLD, derived_with_keys=off
+--echo #
+
+CREATE TABLE t1 (l_orderkey int);
+INSERT INTO t1 VALUES (1),(2);
+CREATE TABLE t2 (o_orderkey int);
+INSERT INTO t2 VALUES (3),(4);
+SET IN_PREDICATE_CONVERSION_THRESHOLD= 2;
+SET OPTIMIZER_SWITCH='derived_with_keys=on';
+SELECT * FROM t1 JOIN t2 ON (l_orderkey = o_orderkey) WHERE l_orderkey IN (1, 2, 3);
+SET OPTIMIZER_SWITCH='derived_with_keys=off';
+SELECT * FROM t1 JOIN t2 ON (l_orderkey = o_orderkey) WHERE l_orderkey IN (1, 2, 3);
+SET @@IN_PREDICATE_CONVERSION_THRESHOLD=@@global.IN_PREDICATE_CONVERSION_THRESHOLD;
+SET @@OPTIMIZER_SWITCH=@@global.OPTIMIZER_SWITCH;
+DROP TABLE t1, t2;
+
+--echo #
 --echo # End of 11.0 tests
 --echo #
diff --git a/mysql-test/main/func_group.result b/mysql-test/main/func_group.result
index 1e0fd660189..82107de4657 100644
--- a/mysql-test/main/func_group.result
+++ b/mysql-test/main/func_group.result
@@ -1821,7 +1821,7 @@ CREATE TABLE t1(f1 YEAR(4));
 INSERT INTO t1 VALUES (0000),(2001);
 (SELECT MAX(f1) FROM t1) UNION (SELECT MAX(f1) FROM t1);
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				MAX(f1)	MAX(f1)	13	4	4	Y	32864	0	63
+def				MAX(f1)	MAX(f1)	13	4	4	Y	49248	0	63
 MAX(f1)
 2001
 DROP TABLE t1;
diff --git a/mysql-test/main/metadata.result b/mysql-test/main/metadata.result
index 5786e2fd461..ab28cab52cb 100644
--- a/mysql-test/main/metadata.result
+++ b/mysql-test/main/metadata.result
@@ -147,7 +147,7 @@ id	data	data
 2	female	no
 select t1.id from t1 union select t2.id from t2;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				id	id	246	4	1	Y	32768	0	63
+def				id	id	246	4	1	Y	49152	0	63
 id
 1
 2
@@ -158,7 +158,7 @@ insert into t1 values (2,'two');
 set @arg00=1 ;
 select @arg00 FROM t1 where a=1 union distinct select 1 FROM t1 where a=1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				@arg00	@arg00	8	20	1	Y	32768	0	63
+def				@arg00	@arg00	8	20	1	Y	49152	0	63
 @arg00
 1
 select * from (select @arg00) aaa;
@@ -168,12 +168,12 @@ def			aaa	@arg00	@arg00	8	20	1	Y	32768	0	63
 1
 select 1 union select 1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				1	1	3	1	1	N	32769	0	63
+def				1	1	3	1	1	N	49153	0	63
 1
 1
 select * from (select 1 union select 1) aaa;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def			aaa	1	1	3	1	1	N	32769	0	63
+def			aaa	1	1	3	1	1	N	49153	0	63
 1
 1
 drop table t1;
diff --git a/mysql-test/main/mysql_client_test.result b/mysql-test/main/mysql_client_test.result
index dbc1feaa23b..e32053e50f3 100644
--- a/mysql-test/main/mysql_client_test.result
+++ b/mysql-test/main/mysql_client_test.result
@@ -130,7 +130,7 @@ mysql_stmt_next_result(): 0; field_count: 0
 # cat MYSQL_TMP_DIR/test_mdev26145.out.log
 # ------------------------------------
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				MAX(a)	MAX(a)	3	11	0	Y	32768	0	63
+def				MAX(a)	MAX(a)	3	11	0	Y	49152	0	63
 # ------------------------------------
 
 
diff --git a/mysql-test/main/type_enum.result b/mysql-test/main/type_enum.result
index 9e313f5b302..a935e3d63cb 100644
--- a/mysql-test/main/type_enum.result
+++ b/mysql-test/main/type_enum.result
@@ -2377,7 +2377,7 @@ t2	CREATE TABLE `t2` (
 DROP TABLE t2;
 SELECT c_int FROM t1 UNION SELECT c_enum FROM t1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				c_int	c_int	253	11	0	Y	0	0	8
+def				c_int	c_int	253	11	0	Y	16384	0	8
 c_int
 SELECT COALESCE(c_int, c_enum)  FROM t1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
diff --git a/mysql-test/main/type_set.result b/mysql-test/main/type_set.result
index 571e0d36eaf..5821bbae984 100644
--- a/mysql-test/main/type_set.result
+++ b/mysql-test/main/type_set.result
@@ -403,7 +403,7 @@ t2	CREATE TABLE `t2` (
 DROP TABLE t2;
 SELECT c_int FROM t1 UNION SELECT c_set FROM t1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				c_int	c_int	253	33	0	Y	0	0	33
+def				c_int	c_int	253	33	0	Y	16384	0	33
 c_int
 SELECT COALESCE(c_int, c_set)  FROM t1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index 188f98aa7dd..e77023f1fd3 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -354,8 +354,6 @@ select_unit::create_result_table(THD *thd_arg, List<Item> *column_types,
     return TRUE;
 
   table->keys_in_use_for_query.clear_all();
-  for (uint i=0; i < table->s->fields; i++)
-    table->field[i]->flags &= ~(PART_KEY_FLAG | PART_INDIRECT_KEY_FLAG);
 
   if (create_table)
   {
@@ -393,9 +391,6 @@ select_union_recursive::create_result_table(THD *thd_arg,
     return true;
 
   incr_table->keys_in_use_for_query.clear_all();
-  for (uint i=0; i < table->s->fields; i++)
-    incr_table->field[i]->flags &= ~(PART_KEY_FLAG | PART_INDIRECT_KEY_FLAG);
-
   return false;
 }