And as specifically noted in that linked article you reference, it talks about how functional dependencies are a feature of SQL-99.
This aspect of the original article is really talking about how MySQL decided to implement a more up-to-date version of the spec that many competitors when they finally addresses their deficiency (as well they should, finally being SQL-92 compliant in the 2010's wouldn't really be anything to boast about).
This aspect of the original article is really talking about how MySQL decided to implement a more up-to-date version of the spec that many competitors when they finally addresses their deficiency (as well they should, finally being SQL-92 compliant in the 2010's wouldn't really be anything to boast about).