Re: Calculage avg. width when operator = is missing

On Tue, Sep 22, 2015 at 11:17 PM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
wrote:

> Shulgin, Oleksandr wrote:
> > On Sep 22, 2015 8:58 PM, "Andrew Dunstan" <andrew(at)dunslane(dot)net> wrote:
>
> > > Yes, "/revenons/ à /nos moutons/." You can set up text based comparison
> > > ops fairly easily for json - you just need to be aware of the
> limitations.
> > > See https://gist.github.com/adunstan/32ad224d7499d2603708
> >
> > Yes, I've already tried this approach and have found that analyze
> > performance degrades an order of magnitude due to sql-level function
> > overhead and casts to text. In my tests, from 200ms to 2000ms with btree
> > ops on a default sample of 30,000 rows.
>
> You should be able to create a C function json_cmp() that simply calls
> bttextcmp() internally, and C functions for each operator using that
> one, in the same way.
>

Yes, but I didn't try this because of the requirement to
compile/install/maintain the externally loadable module. If I could just
use CREATE FUNCTION on a postgres' internal function such as texteq or
bttextcmp (with obj_file of NULL, for example) I would definitely do that.
:-)

--
Alex