Rough impl of IGNORE NULLS for window functions - Mailing list pgsql-hackers

From Joe Banafato
Subject Rough impl of IGNORE NULLS for window functions
Date
Msg-id CAL2X8+Pd146bxzYWq+iN9WTnN5z-skHi3EgGg4nGrg7EytnjFw@mail.gmail.com
Whole thread Raw
Responses Re: Rough impl of IGNORE NULLS for window functions
List pgsql-hackers
Hi all,

I wrote an implementation of last_value that ignores null values,
effectively achieving the behavior of last_value(<exp> ignore nulls).
The code is up on BitBucket [1] for the moment.  Thoughts:

* This isn't on the TODO [2].  Is anyone interested in getting this in
the language?  I use this feature extensively and need it for an
Oracle port.
* I'd love to get a critique, especially on using WinSetMarkPosition.
* I have not extended the syntax (I simply called the function
last_value_ignore_nulls), and I hope to get some guidance on starting
that.

I'll be starting the other functions shortly.

Cheers,

Joe

[1] https://bitbucket.org/joeb/pg-window-ignore-nulls/src
[2] https://wiki.postgresql.org/wiki/Todo#Window_Functions


pgsql-hackers by date:

Previous
From: Amit Kapila
Date:
Subject: Re: cheaper snapshots redux
Next
From: panam
Date:
Subject: Re: fix for pg_upgrade