Bug #108129 query with where lost connection after renaming column to lowercase from upper
Submitted: 12 Aug 2022 9:38 Modified: 18 Aug 2022 15:41
Reporter: Sucre Sucre Email Updates:
Status: Can't repeat Impact on me:
None 
Category:MySQL Cluster NDB Operator Severity:S2 (Serious)
Version:8.0.21 OS:Red Hat (oracle linux7)
Assigned to: MySQL Verification Team CPU Architecture:x86

[12 Aug 2022 9:38] Sucre Sucre
Description:
Query with where clause got connection lost after renaming column from upper to lowercase.

How to repeat:
mysql> create table `t2` (`id` bigint not null auto_increment primary key, `BUG` varchar(64)) engine=ndbcluster;
Query OK, 0 rows affected (0.31 sec)

mysql> insert into t2(id) value(null);
Query OK, 1 row affected (0.00 sec)

mysql> select * from t2;
+----+------+
| id | BUG  |
+----+------+
|  1 | NULL |
+----+------+
1 row in set (0.01 sec)

mysql> select * from t2 where BUG is null;
+----+------+
| id | BUG  |
+----+------+
|  1 | NULL |
+----+------+
1 row in set (0.00 sec)

mysql> alter table t2 rename column BUG to bug;
Query OK, 0 rows affected (4.23 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> select * from t2 where BUG is null;
ERROR 2013 (HY000): Lost connection to MySQL server during query
mysql>

Suggested fix:
na
[15 Aug 2022 7:11] Sucre Sucre
mysql> select * from t2 where bug is null;
ERROR 2013 (HY000): Lost connection to MySQL server during query
mysql>
[18 Aug 2022 15:41] MySQL Verification Team
Hi,

I cannot reproduce this with 8.0.29

node1 [localhost:29930] {msandbox} (test) > create table `t2` (`id` bigint not null auto_increment primary key, `BUG` varchar(64)) engine=ndbcluster;
Query OK, 0 rows affected (0.81 sec)

node1 [localhost:29930] {msandbox} (test) >  insert into t2(id) value(null);
Query OK, 1 row affected (0.04 sec)

node1 [localhost:29930] {msandbox} (test) > select * from t2;
+----+------+
| id | BUG  |
+----+------+
|  1 | NULL |
+----+------+
1 row in set (0.01 sec)

node1 [localhost:29930] {msandbox} (test) > select * from t2 where BUG is null;
+----+------+
| id | BUG  |
+----+------+
|  1 | NULL |
+----+------+
1 row in set (0.00 sec)

node1 [localhost:29930] {msandbox} (test) > alter table t2 rename column BUG to bug;
Query OK, 0 rows affected (0.30 sec)
Records: 0  Duplicates: 0  Warnings: 0

node1 [localhost:29930] {msandbox} (test) > select * from t2 where BUG is null;
+----+------+
| id | bug  |
+----+------+
|  1 | NULL |
+----+------+
1 row in set (0.00 sec)

node1 [localhost:29930] {msandbox} (test) > select @@version
    -> ;
+----------------+
| @@version      |
+----------------+
| 8.0.29-cluster |
+----------------+
1 row in set (0.00 sec)