Re: postgresql versus riak for a global exchange

I’m familiar with both PostgreSQL and Riak (1.4, not 2.0).
I know that Riak 2.0 now offers strong consistency. Have not yet seen what that does to performance.
Big plusses for PostgreSQL:
- you can do both relational and NOSQL tasks (the Binary JSON in the latest PostgreSQL).
- well-tested consistency, ACID, etc.
- lots of adapters and support.
- big community

Big plusses for Riak:
- multi-master replication
- multi-data center replication
- easy to scale up

We use PostgreSQL in combination with Riak for data storage (we have a tokenization service).
We're currently using the EnterpriseDB multi-master PostgreSQL replication and are quite happy with it.
The replication runs periodically, not streaming, so there is at least a 1 second delay for replication to occur.
Riak replicates quicker — but then you don’t have the strong relational structure on top.

As mentioned earlier, ‘exchange…trade…asset’ is a bit vague.
In addition to just storing things, you’ll need to keep track of all sorts of log-in and contact info — perhaps not ideal for Riak.
Probably best to consider precisely what traits your planned application has and then look to match against the database storage.
May even end up with a mix of the two just as we have.

Your decision may also depend on which development language/framework you chose for the implementation.

—Ray

> On Jan 5, 2015, at 11:37 AM, xu xiut <xiut(dot)xu(at)gmail(dot)com> wrote:
>
> Hello, I am looking at creating a toy project which may turn into an actual business if I'm lucky, the ideal is generally just an exchange for people to trade some type of asset.
>
> I'm looking at using either PostgreSQL or Riak, and I'm wondering if there are opinions and suggestions that someone would be willing to share with me when evaluating databases.
>
> This is the first time I've actually considered something besides PostgreSQL. Riak 2.0 now offers strong consistency and I really respect the community and the work that has gone into the project. It seems like it would be easy to replicate across multiple data centers.
>
> Thanks for letting me ask this here!