Suppose your library consists of 3 films:
Film A: Release Date: December 10th, 2000; Year: 2000
Film B: Release Date: ; Year: 2000
Film C: Release Date: September 18th, 1999; Year 1999
When sorting by release date descending, the expected order would be either A B C or B A C (sorting Film B as somewhere in the year 2000, although its release date is blank), but the actual order is A C B (because its release date is blank).
This bug could be fixed by making SORT BY releasedate DESC be SORT BY releasedate DESC, year DESC.
