Interesting, another use of a SQL-like language as the query language for a data store that's definitely not an SQL database. (YQL is another example.) I really don't understand why ORMs always seem to want to create their an object-based query language--SQL is just fine for querying.
It's difficult to provide tooling for SQL in a way that provides a good experience for the user. For example, providing auto-completion in a SELECT statement is hard because attributes are specified before the tables which contain them are declared, leading to a-more-annoying-than-it-should-be editing experience.
