şayet Milyonlarca araç üzerinde sorgulama konulemi binayorsak zahir IQueryable IEnumerable nazaran elan hızlı sorgulama işlemlemi yapar. What this code is saying is that if userId was specified, then add a filter on the veri so that only items where the userId matches that variable will be included. That same thing https://cobjectkullanm43406.national-wiki.com/778050/the_ultimate_guide_to_c_ienumerable_nasıl_kullanılır