On 02/28/2014 02:00 PM, Tom Lane wrote:
Peter Geoghegan <p...@heroku.com> writes:
On Fri, Feb 28, 2014 at 5:01 AM, Andrew Dunstan <and...@dunslane.net> wrote:
But anyway, I think we've seen enough of these to conclude that the casts
from hstore to jsonb and back should not be implicit. I am fairly confident
that changing that would fix your complaint and the similar one that Peter
Geoghegan had.
Yes, it will, but I think that that will create more problems than it
will solve (which is not to suggest that an implicit cast is the right
thing). That will require that any non-trivial usage of jsonb requires
copious casting, where nested hstore does not. The hstore module
hardly contains some nice extras that a minority of jsonb users will
be interested in. It contains among other basic things, operator
classes required to index jsonb. All of my examples will still not
work, plus a bunch of cases that currently do work reasonably well.
There'll just be a different error message.
We should have learned by now that implicit casts are generally pretty
dangerous things. I think putting in implicit casts as a band-aid for
missing functionality is a horrid idea that we'll regret for a long
time to come. I gather from upthread comments that the patch currently
actually creates implicit casts in *both* directions? That's doubly
horrid/dangerous.
I agree. I have removed them in my current tree.
The more I read in this thread, the more I think that jsonb simply
isn't ready. We should put it off to 9.5 so that we can have a
complete implementation without so many rough edges. I'm afraid that
if we ship it as-is, backwards compatibility considerations are going
to prevent us from filing down the rough edges in future.
Well, the jsonb portion of this is arguably the most ready, certainly
it's had a lot more on-list review.
cheers
andrew
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
