Thanks - I've added it here: .

I've also attached a revised version that makes IGNORE and RESPECT
UNRESERVED keywords (following the pattern of NULLS_FIRST and NULLS_LAST).


On 23 March 2013 14:34, Tom Lane <> wrote:

> Nicholas White <> writes:
> > The SQL standard defines a RESPECT NULLS or IGNORE NULLS option for lead,
> > lag, [...]. This is not implemented in PostgreSQL
> > (
> > I've had a go at implementing this, and I've attached the resulting
> patch.
> > It's not finished yet, but I was hoping to find out if my solution is
> along
> > the right lines.
> Since we're trying to get 9.3 to closure, this patch probably isn't
> going to get much attention until the 9.4 development cycle starts
> (in a couple of months, likely).  In the meantime, please add it to
> the next commitfest list so we remember to come back to it:
> One comment just from a quick eyeball look is that we really hate
> adding new keywords that aren't UNRESERVED, because that risks
> breaking existing applications.  Please see if you can refactor the
> grammar to make those new entries unreserved.
>                         regards, tom lane

Attachment: lead-lag-ignore-nulls.patch
Description: Binary data

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