Re: Fix for FETCH FIRST syntax problems

On 20/05/18 00:57, Tom Lane wrote:
> Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)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.

It certainly does. It allows this now:

PREPARE foo AS TABLE bar FETCH FIRST $1 ROWS ONLY;

>> 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.
I'm +1 for backpatching it. It may be operating as designed by PeterE
ten years ago, but it's not operating as designed by the SQL standard.
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