Bug #106225 select bin("") should return 0 instead of null

• Submitted: 20 Jan 2022 9:54
• Modified: 20 Jan 2022 10:14
• Reporter: Huaiyu Xu
• Status: Verified
• Category: MySQL Server: DML
• Severity: S3 (Non-critical)
• Version: 5.7, 8.0, 8.0.32
• OS: Any
• CPU Architecture: Any

[20 Jan 2022 9:54] Huaiyu Xu

Description:
mysql> select bin(cast("" as unsigned));
+---------------------------+
| bin(cast("" as unsigned)) |
+---------------------------+
| 0                         |
+---------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> select bin("");
+---------+
| bin("") |
+---------+
| NULL    |
+---------+
1 row in set (0.00 sec)

How to repeat:
mysql> select bin(cast("" as unsigned));
+---------------------------+
| bin(cast("" as unsigned)) |
+---------------------------+
| 0                         |
+---------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> select bin("");
+---------+
| bin("") |
+---------+
| NULL    |
+---------+
1 row in set (0.00 sec)

Suggested fix:
`select bin("")` should also return 0

[20 Jan 2022 10:14] MySQL Verification Team

Hello Huaiyu Xu,

Thank you for the report and test case.

regards,
Umesh