Re: Fetch zero result rows when executing a query?

On 2015-02-04 12:23:51 +0100, Marko Tiikkaja wrote:
> On 2/4/15 12:13 PM, Stephen R. van den Berg wrote:
> >If you know beforehand the query might generate more than one row (SELECT)
> >yet you also know that you are not interested in those, then maxrows=1
> >is best; then again, modifying the query to include a LIMIT 1 is even
> >better, in which case maxrows can be zero again.
> 
> This seems to be a common pattern, and I think it's a *huge* mistake to
> specify maxrows=1 and/or ignore rows after the first one in the driver
> layer.  If the user says "give me the only row returned by this query", the
> interface should check that only one row is in reality returned by the
> query

I don't think these are what this thread is about. It's about a UPDATE
(=> no LIMIT) where the user uses a driver interface that doesn't return
rows generated by the UPDATE (the above error check doesn't make sense).

Greetings,

Andres Freund

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