Bug#22186926: CONVERT_CONSTANT_ITEM(THD*, ITEM_FIELD*, ITEM**): ASSERTION `!RESULT' FAILED.

Problem statement uses MAX/MIN optimization in opt_sum_query.
Index access is used to check if optmization is possible and
datetime column is not present in the index. So datetime field
is unread after optmization. In convert_constant_item()
incorrect value is obtained from the field since field is not
evaluated. Attempt to store this incorrect value to the field
later leads to assert failure.

Author: Sergey Glukhov

mysql-test/r/group_by.result

@@ -3247,3 +3247,29 @@ WHERE b.b = c.b
 GROUP BY c.c;
 ERROR 42000: Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'test.a.b' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
 DROP TABLE t1;
+#
+# Bug #22186926 CONVERT_CONSTANT_ITEM(THD*, ITEM_FIELD*, ITEM**): ASSERTION `!RESULT' FAILED.
+#
+CREATE TABLE t1
+(
+f1 INTEGER NOT NULL,
+f2 DATETIME NOT NULL,
+f3 VARCHAR(1) NOT NULL,
+KEY (f3)
+);
+INSERT INTO t1(f1, f2, f3) VALUES
+(5, '2001-07-25 08:40:24.058646', 'j'),
+(2, '1900-01-01 00:00:00', 's'),
+(4, '2001-01-20 12:47:23.022022', 'x');
+CREATE TABLE t2 (f1 VARCHAR(1) NOT NULL);
+FLUSH TABLES;
+EXPLAIN SELECT MIN(t1.f3 ) FROM t1
+WHERE t1.f3 IN (SELECT t2.f1 FROM t2 WHERE NOT t1.f2 IS NOT NULL) AND t1.f1 IS NULL OR
+NOT t1 . f3 < 'q';
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
+Warnings:
+Note	1276	Field or reference 'test.t1.f2' of SELECT #2 was resolved in SELECT #1
+Note	1003	/* select#1 */ select min(`test`.`t1`.`f3`) AS `MIN(t1.f3 )` from `test`.`t1` where (`test`.`t1`.`f3` >= 'q')
+DROP TABLE t1,t2;

mysql-test/t/group_by.test

@@ -2435,3 +2435,31 @@ GROUP BY c.c;
 
 DROP TABLE t1;
 
+--echo #
+--echo # Bug #22186926 CONVERT_CONSTANT_ITEM(THD*, ITEM_FIELD*, ITEM**): ASSERTION `!RESULT' FAILED.
+--echo #
+
+CREATE TABLE t1
+(
+  f1 INTEGER NOT NULL,
+  f2 DATETIME NOT NULL,
+  f3 VARCHAR(1) NOT NULL,
+  KEY (f3)
+);
+
+INSERT INTO t1(f1, f2, f3) VALUES
+(5, '2001-07-25 08:40:24.058646', 'j'),
+(2, '1900-01-01 00:00:00', 's'),
+(4, '2001-01-20 12:47:23.022022', 'x');
+
+
+CREATE TABLE t2 (f1 VARCHAR(1) NOT NULL);
+
+FLUSH TABLES;
+
+EXPLAIN SELECT MIN(t1.f3 ) FROM t1
+WHERE t1.f3 IN (SELECT t2.f1 FROM t2 WHERE NOT t1.f2 IS NOT NULL) AND t1.f1 IS NULL OR
+  NOT t1 . f3 < 'q';
+
+
+DROP TABLE t1,t2;

sql/opt_sum.cc

@@ -451,6 +451,14 @@ int opt_sum_query(THD *thd,
                  get_index_min_value(table, &ref, item_field, range_fl,
                                      prefix_len);
 
+          /*
+            Set TABLE::status to STATUS_GARBAGE since original and
+            real read_set are different, i.e. some field values
+            from original read set could be unread.
+          */
+          if (!bitmap_is_subset(&table->def_read_set, &table->tmp_set))
+            table->status|= STATUS_GARBAGE;
+
           table->read_set= &table->def_read_set;
           bitmap_clear_all(&table->tmp_set);
           /* Verify that the read tuple indeed matches the search key */