-
Type:
Bug
-
Status: Closed (View Workflow)
-
Priority:
Minor
-
Resolution: Fixed
-
Affects Version/s: 5.5, 10.1, 10.2, 10.3, 10.2.13, 10.0
-
Fix Version/s: 5.5.60
-
Component/s: Optimizer
-
Labels:
-
Environment:docker with mariadb:latest (host is a debian testing)
10.2.13-MariaDB (tested on docker latest)
MariaDB [(none)]> SELECT 1 from DUAL WHERE 1 != 1; |
Empty set (0.00 sec) |
Ok.
Exhibit A :
MariaDB [(none)]> SELECT 2 IN (SELECT 1 from DUAL WHERE 1 != 1); |
+----------------------------------------+ |
| 2 IN (SELECT 1 from DUAL WHERE 1 != 1) | |
+----------------------------------------+ |
| 0 |
|
+----------------------------------------+ |
|
|
1 row in set (0.00 sec) |
Ok.
2 is indeed not in the empty set
Exhibit B :
MariaDB [(none)]> SELECT 2 IN (SELECT 2 from DUAL WHERE 1 != 1); |
+----------------------------------------+ |
| 2 IN (SELECT 2 from DUAL WHERE 1 != 1) | |
+----------------------------------------+ |
| 1 |
|
+----------------------------------------+ |
|
|
1 row in set (0.00 sec) |
Not ok.
I thought 2 was not in emptyset. why changing the emptyset did affect that ?
Exhibit B looks like a DUAL bug, as :
- it returns 0 if we replace DUAL by any other table
- it returns 0 if I use a mysql backend instead