Re: jsonb format is pessimal for toast compression

On Thu, Sep 25, 2014 at 09:00:07PM +0200, Andres Freund wrote:
> On 2014-09-25 14:46:18 -0400, Bruce Momjian wrote:
> > On Thu, Sep 25, 2014 at 02:39:37PM -0400, Tom Lane wrote:
> > > BTW, it seems like there is consensus that we ought to reorder the items
> > > in a jsonb object to have keys first and then values, independently of the
> > > other issues under discussion.  This means we *will* be breaking on-disk
> > > compatibility with 9.4beta2, which means pg_upgrade will need to be taught
> > > to refuse an upgrade if the database contains any jsonb columns.  Bruce,
> > > do you have time to crank out a patch for that?
> > 
> > Yes, I can do that easily.  Tell me when you want it --- I just need a
> > catalog version number to trigger on.
> 
> Do you plan to make it conditional on jsonb being used in the database?
> That'd not be bad to reduce the pain for testers that haven't used jsonb.

Yes, I already have code that scans pg_attribute looking for columns
with problematic data types and output them to a file, and then throw an
error.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + Everyone has their own god. +