layout title permalink page Language /language/ Slides pdf git v1.4.1 Videos playlist 2h7m39s introduction yt up base language introduction yt up integrity constraints yt up choice rules yt up cardinality rules yt up weight rules yt up conditional literals yt up optimization yt up formats yt up input terms and literals yt up rules and aggregates yt up directives yt up intermediate yt up summary yt up Extras aggregates pdf Exercise sheets pdf git v1.1.0