On Fri, Oct 17, 2014 at 7:45 PM, Merlin Moncure <mmoncure@gmail.com> wrote:
On Wed, Oct 15, 2014 at 3:48 AM, Atri Sharma <atri.jiit@gmail.com> wrote: > > > On Wednesday, October 15, 2014, Marti Raudsepp <marti@juffo.org> wrote: >> >> Hi >> >> On Wed, Oct 15, 2014 at 11:02 AM, Atri Sharma <atri.jiit@gmail.com> wrote: >> > Please find attached a patch which implements support for UPDATE table1 >> > SET(*)=... >> >> I presume you haven't read Tom Lane's proposal and discussion about >> multiple column assignment in UPDATE: >> http://www.postgresql.org/message-id/1783.1399054541@sss.pgh.pa.us >> (Assigning all columns was also discussed there) >> >> And there's a WIP patch: >> http://www.postgresql.org/message-id/20930.1402931841@sss.pgh.pa.us > > Thanks for the links, but this patch only targets SET(*) case, which, if I > understand correctly, the patch you mentioned doesn't directly handle (If I > understand correctly, the target of the two patches is different).
Yeah -- in fact, there was some discussion about this exact case. This patch solves a very important problem: when doing record operations to move data between databases with identical schema there's currently no way to 'update' in a generic way without building out the entire field list via complicated and nasty dynamic SQL.
Thanks!
I'm not sure about the proposed syntax though; it seems a little weird to me. Any particular reason why you couldn't have just done:
UPDATE table1 SET * = a,b,c, ...
also,
UPDATE table1 t SET t = (SELECT (a,b,c)::t FROM...);
I honestly have not spent a lot of time thinking about the exact syntax that may be acceptable. If we have arguments for or against a specific syntax, I will be glad to incorporate them.