Re: FETCH FIRST clause WITH TIES option - Mailing list pgsql-hackers

From Andrew Gierth
Subject Re: FETCH FIRST clause WITH TIES option
Date
Msg-id 87a73mn4cl.fsf@news-spur.riddles.org.uk
Whole thread Raw
In response to Re: FETCH FIRST clause WITH TIES option  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: FETCH FIRST clause WITH TIES option
List pgsql-hackers
>>>>> "Alvaro" == Alvaro Herrera <alvherre@2ndquadrant.com> writes:

 Alvaro> It turns out that the SQL standard is much more limited in what
 Alvaro> it will accept there. But our grammar (what we'll accept for
 Alvaro> the ancient LIMIT clause) is very lenient -- it'll take just
 Alvaro> any expression. I thought about reducing that to NumericOnly
 Alvaro> for FETCH FIRST .. WITH TIES, but then I have to pick: 1)
 Alvaro> gram.y fails to compile because of a reduce/reduce conflict, or
 Alvaro> 2) also restricting FETCH FIRST .. ONLY to NumericOnly. Neither
 Alvaro> of those seemed very palatable.

FETCH FIRST ... ONLY was made _too_ restrictive initially, such that it
didn't allow parameters (which are allowed by the spec); see 1da162e1f.

(That change didn't present a problem for ruleutils, because FETCH FIRST
... ONLY is output as a LIMIT clause instead.)

This needs to be fixed in ruleutils, IMO, not by changing what the
grammar accepts.

-- 
Andrew.



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