DDL is a bit curious, because it’s less a programming language and more of a set of configuration and operational commands. It just happens to look similar to D

DDL is a bit curious, because it’s less a programming language and more of a set of configuration and operational commands. It just happens to look similar to DQL, but there’s nothing really pushing that beyond the fact that DDL can rely on DQL as a subexpression (eg create view as …). You could probably say the relationship between DQL and DDL is largely aesthetic The only reason I can think of where you often can’t strictly treat DQL and DDL as totally different languages is the just from the total lack of interest in consistency in SQL language design generally — eg update and delete steal parts of DML syntax haphazardly and differently; the syntax for update/delete data referring to another table UPDATE table WHERE … JOIN … vs DELETE FROM table USING … The lack of complexity in DDL generally (its very wide, but not very deep; there’s not much meaningful composition to be discussed) and its lack of a real relationship to DQL is probably why no one discusses it much