Re: Calculage avg. width when operator = is missing

Shulgin, Oleksandr wrote:
> On Sep 22, 2015 8:58 PM, "Andrew Dunstan" <andrew@dunslane.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.

In any case I think your patch is a good starting point.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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