Re: BUG #12000: "CROSS JOIN" not equivalent to ","

David G Johnston wrote:

> I personally find the use of "," in the FROM-clause to be poor form and its
> even worse if you decide to mix both "," and explicit JOIN clauses.  If you
> want to make this be explained better feel free to provide suggestions; but
> I'd suggest you simply forget the fact that "FROM A, B" is even valid and
> just use the proper joining keywords instead.

Note that using explicit join form force the optimizer into some
specific join order, depending on the join_collapse_limit parameter,
whereas using commas gives it absolute freedom regardless of the
parameter.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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