Re: SQL/JSON revisited

On 2023-Mar-29, Alvaro Herrera wrote:

> In the meantime, here's the next two patches of the series: IS JSON and
> the "query" functions.  I think this is as much as I can get done for
> this release, so the last two pieces of functionality would have to wait
> for 17.  I still need to clean these up some more.  These are not
> thoroughly tested either; 0001 compiles and passes regression tests, but
> I didn't verify 0003 other than there being no Git conflicts and bison
> doesn't complain.
> 
> Also, notable here is that I realized that I need to backtrack on my
> change of the WITHOUT_LA: the original patch had it for TIME (in WITHOUT
> TIME ZONE), and I changed to be for UNIQUE.  But now that I've done
> "JSON query functions" I realize that it needed to be the other way for
> the WITHOUT ARRAY WRAPPER clause too.  So 0002 reverts that choice.

So I pushed 0001 on Friday, and here are 0002 (which I intend to push
shortly, since it shouldn't be controversial) and the "JSON query
functions" patch as 0003.  After looking at it some more, I think there
are some things that need to be addressed by one of the authors:

- the gram.y solution to the "ON ERROR/ON EMPTY" clauses is quite ugly.
  I think we could make that stuff use something similar to
  ConstraintAttributeSpec with an accompanying post-processing function.
  That would reduce the number of ad-hoc hacks, which seem excessive.

- the changes in formatting.h have no explanation whatsoever.  At the
  very least, the new function should have a comment in the .c file.
  (And why is it at end of file?  I bet there's a better location)

- some nasty hacks are being used in the ECPG grammar with no tests at
  all.  It's easy to add a few lines to the .pgc file I added in prior
  commits.

- Some functions in jsonfuncs.c have changed from throwing hard errors
  into soft ones.  I think this deserves more commentary.

- func.sgml: The new functions are documented in a separate table for no
  reason that I can see.  Needs to be merged into one of the existing
  tables.  I didn't actually review the docs.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
"I'm impressed how quickly you are fixing this obscure issue. I came from 
MS SQL and it would be hard for me to put into words how much of a better job
you all are doing on [PostgreSQL]."
 Steve Midgley, http://archives.postgresql.org/pgsql-sql/2008-08/msg00000.php