Thread: PostgreSQL 9.0 - support for RANGE value PRECEDING window functions
Hi, I have a question about a feature in PostgreSQL 9.0. I am looking for support for windowing functions when using: RANGE BETWEEN <value> PRECEDING/FOLLOWING AND <value> PRECEDING/FOLLOWING The latest documentation: http://www.postgresql.org/docs/9.0/static/sql-expressions.html#SYNTAX-WINDOW-FUNCTIONS Says "The value PRECEDING and value FOLLOWING cases are currently only allowed in ROWS mode." However, I have found this post: http://archives.postgresql.org/message-id/e08cc0400912310149me7150cek3c9aa92e4d396ac3@mail.gmail.com Which appears to provide a patch supporting: "- allow all of RANGE BETWEEN <value> PRECEDING/FOLLOWING AND <value> PRECEDING/FOLLOWING". However, I cannot find any further information related to this feature. Can anyone confirm whether or not this feature will be available in PostgreSQL 9.0? Thanks, Dan Scott
Excerpts from Daniel Scott's message of lun may 10 13:20:06 -0400 2010: > Says "The value PRECEDING and value FOLLOWING cases are currently only > allowed in ROWS mode." > > However, I have found this post: > > http://archives.postgresql.org/message-id/e08cc0400912310149me7150cek3c9aa92e4d396ac3@mail.gmail.com > > Which appears to provide a patch supporting: "- allow all of RANGE > BETWEEN <value> PRECEDING/FOLLOWING AND <value> > PRECEDING/FOLLOWING". However, I cannot find any further information > related to this feature. It was ripped out of the patch before commit because the implementation was not acceptable. > Can anyone confirm whether or not this feature will be available in > PostgreSQL 9.0? No. --
Hi, On Mon, May 10, 2010 at 13:35, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote: > It was ripped out of the patch before commit because the implementation was not > acceptable. That's strange - the CommitFest says that it was committed and I can't find any mention of it being removed. Is there somewhere I can see a discussion of this? https://commitfest.postgresql.org/action/commitfest_view?id=5 Also, the documentation http://www.postgresql.org/docs/9.0/static/sql-expressions.html#SYNTAX-WINDOW-FUNCTIONS shows: [ RANGE | ROWS ] BETWEEN frame_start AND frame_end Can you point me to the right place for getting this changed to remove "RANGE". Maybe the developer mailing list? Thanks, Dan Scott
Daniel Scott <djscott@mit.edu> writes: > On Mon, May 10, 2010 at 13:35, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote: >> It was ripped out of the patch before commit because the implementation was not >> acceptable. > That's strange - the CommitFest says that it was committed and I can't > find any mention of it being removed. Is there somewhere I can see a > discussion of this? Look into the pgsql-hackers thread about it. (The commitfest notes are not meant to be a complete record of the mailing list discussions.) I think the relevant part starts here: http://archives.postgresql.org/pgsql-hackers/2010-02/msg00540.php > Also, the documentation > http://www.postgresql.org/docs/9.0/static/sql-expressions.html#SYNTAX-WINDOW-FUNCTIONS > shows: > [ RANGE | ROWS ] BETWEEN frame_start AND frame_end > Can you point me to the right place for getting this changed to remove > "RANGE". Maybe the developer mailing list? There's nothing to remove there, since RANGE is in fact valid with many of the alternatives for frame_start and frame_end. It would be very awkward to try to show this limitation as part of the syntax diagram, so it's just specified in the text. regards, tom lane