Why does updating the same data affect the number of rows by 1

[tss3023coding]

When I update the same data, the number of affected rows is 1. The following is the code:

When I logged in through MySQL client and executed the same update statement, the number of affected lines was 0, as shown in the following figure:

Has anyone encountered the same problem, unsure if it is a bug.

[bclozel]

Thanks for getting in touch, but it feels like this is a question that would be better suited to Stack Overflow. As mentioned in the guidelines for contributing, we prefer to use the issue tracker only for bugs and enhancements. Feel free to update this issue with a link to the re-posted question (so that other people can find it) or add some more details if you feel this is a genuine bug.