Why isn't Delete used here?

[ProgramComputer]

lwt/edit_languages.php

Line 148 in d8e2258

SET LgName = "", LgDict1URI = "", LgDict2URI = "",

There could be an issue for unsupported languages. Create two unsupported languages possible with #150 and delete both or delete two supported languages. The second language can't be deleted due to duplicate key error.

Error message below -

[HugoFara]

I can't see any reason, and it creates a bug. A just added the delete instruction and works fine.