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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>
cc: pgsql-hackers@postgresql.org
Subject: Re: Fix for FETCH FIRST syntax problems
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Comments: In-reply-to Andrew Gierth <andrew@tao11.riddles.org.uk>
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Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
> Attached is a draft patch for fixing that, which additionally fixes the
> ugly wart that OFFSET <x> ROW/ROWS and FETCH FIRST [<x>] ROW/ROWS ONLY
> had very different productions for <x>; both now accept c_expr there.

LGTM, except please s/presense/presence/ in grammar comment.
Also, why'd you back off "must write" to "should write" in the docs?
This doesn't make the parens any more optional than before.

> I think a case can be made that this should be backpatched; thoughts?

Meh, -0.5.  This is not really a bug, because it's operating as designed.
You've found a reasonably painless way to improve the grammar, which is
great, but it seems more like a feature addition than a bug fix.

I'd be fine with sneaking this into v11, though.

			regards, tom lane