You are not able to delete a .wmv file on a wiki on MySQL

Steps to reproduce:

1. Attach a .wmv file to your wiki (more than 2 mb)
2. Press on the delete icon to remove the file
   1. on MySQL you are not able to delete the file, an error appear on your wiki: "Failed to delete attachment: Server Error" and on your console (see the attachment)
   2. on hsqldb, the same file, can be removed