Re: PostgreSQL VS MongoDB: a use case comparison

On Tue, Nov 20, 2018 at 10:43 AM Stephen Frost <sfrost(at)snowman(dot)net> wrote:
>
> Greetings,
>
> * Merlin Moncure (mmoncure(at)gmail(dot)com) wrote:
> > On Mon, Nov 19, 2018 at 11:26 AM Stephen Frost <sfrost(at)snowman(dot)net> wrote:
> > > Looks like a lot of the difference being seen and the comments made
> > > about one being faster than the other are because one system is
> > > compressing *everything*, while PG (quite intentionally...) only
> > > compresses the data sometimes- once it hits the TOAST limit. That
> > > likely also contributes to why you're seeing the on-disk size
> > > differences that you are.
> >
> > Hm. It may be intentional, but is it ideal? Employing datum
> > compression in the 1kb-8kb range with a faster but less compressing
> > algorithm could give benefits.
>
> Well, pglz is actually pretty fast and not as good at compression as
> other things. I could certainly see an argument for allowing a column
> to always be (or at least attempted to be) compressed.
>
> There's been a lot of discussion around supporting alternative
> compression algorithms but making that happen is a pretty big task.

Yeah; pglz is closer to zlib. There's much faster stuff out
there...Andres summed it up pretty well;
https://www.postgresql.org/message-id/20130605150144.GD28067%40alap2.anarazel.de

There are also some interesting discussions on jsonb specific
discussion approaches.

merlin