Re: unclear syntax explanation for multiple window definitions in a SELECT query

This is how we've chosen to document this kind of grammar and I don't see a compelling reason to revisit that decision on the basis of this report.  I could consider some additional wording regarding "each clause keyword only ever appears once in a given (sub)query" though that seems almost self-evident as part of the learning of SQL.  The fact that you write WINDOW and then a comma-separated listing of names plus definitions is how that syntax diagram is read, just like with WITH, FROM, and GROUP BY clauses in the same diagram.

David J.