On 01/09/15 21:41, Bruce Momjian wrote:
>
> Well, reworking our partitioning system is one of the things required
> for sharding, so at least we will clean up one mess while we create
> another. ;-)
>
> Seem my post to Josh Berkus just now --- I think if we don't use FDWs,
> that sharding is such a limited use-case that we will not implement it
> inside of Postgres.
>
I'm thinking that partitioning and sharding are two different things:
Partitioning is about reducing the amount of table data accessed and
also perhaps easing admin activities (archiving/removing old stuff etc).
Sharding is a about parallelism and redundancy...copies of stuff in
different places and concurrent access by virtue of it being on
different nodes!
Now *maybe* FDW is a good way to approach this, but really would be nice
to see a more rigorous analysis (I note that like XC and XL, Greenplum
looked at the existing mechanisms around at the time and ended up
writing their own). Now I'm aware that things have moved on - but I
think there needs to be a proper discussion about design and what we
think distributed data/sharding etc should provide *before* grabbing
hold of FDW as *the answer*!
Regards
Mark