| Bug #119995 | Function find_in_set return wrong result | ||
|---|---|---|---|
| Submitted: | 6 Mar 9:51 | Modified: | 9 Mar 8:51 |
| Reporter: | Jingqi Tian (OCA) | Email Updates: | |
| Status: | Verified | Impact on me: | |
| Category: | MySQL Server: Optimizer | Severity: | S2 (Serious) |
| Version: | 8.0.45 | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
[9 Mar 8:51]
Roy Lyseng
Thank you for the bug report. Verified as described.
[9 Mar 9:55]
Jingqi Tian
Hello, Roy Lyseng, this is my bugfix of bug#119995 based on 9.6.0. (*) I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.
Contribution: bug#119995.diff (application/octet-stream, text), 1.42 KiB.
Description: The function find_in_set may return wrong result. How to repeat: 1. Set collation_connection set collation_connection = 'utf8mb4_0900_ai_ci'; 2. Execute query select find_in_set('ắ', 'a'); +-------------------------+ | find_in_set('ắ', 'a') | +-------------------------+ | 0 | +-------------------------+ However, when the collation_connection is 'utf8mb4_0900_ai_ci', 'ắ' should be equal to 'a'. The result should be 1. To further prove that this is a bug, we can test: select find_in_set('ắ', 'a,b,c'); +-----------------------------+ | find_in_set('ắ', 'a,b,c') | +-----------------------------+ | 1 | +-----------------------------+ The result is 1. Clearly, 'ắ' should be equal to 'a'.