Tom Lane wrote:
Russell Smith <[EMAIL PROTECTED]> writes:
In-equality transformations do not guarantee that y > 1.5x == y/x >
1.5. This is only true for x>0, y < 1.5*x for x<0. I have not posted a
patch as I'm not sure what is the best way to change the example.
Seems a bit nit-picky, but we could change the example to
I would agree, it's nit-picky. But lots of people rely on the truth of
the documentation. People say I have any y/x > z situation, PostgreSQL
manual says it works better if I do y > z*x. So they do it, no
questions asked. Which is the real fear from my point of view.
SELECT ... WHERE x > 0 AND y/x > 1.5;
becomes
SELECT ... WHERE CASE WHEN x > 0 THEN y/x > 1.5 ELSE false END;
regards, tom lane
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