Not specifically commenting on the bitmask approach but with the more general mechanismdont your views end up as massive nested statements. ie: select (select value from EAV where id=? and name='Title') as Title,(select value from EAV where id=? and name='Forenames') as Forenames,(select value from EAV where id=? and name='Surname') as Surname

Where performance is always going to be n * worse than a standard view where n is the number of columns retrieved. Or am I missing something?

I still maintain that database engines are very going at doing this kind of operation under the hood but poor at surfacing it via SQL