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
idealfor Riak.  
Probably best to consider precisely what traits your planned application has and then look to match against the
databasestorage.  
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.xu@gmail.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
generallyjust 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
wouldbe 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
andI really respect the community and the work that has gone into the project. It seems like it would be easy to
replicateacross multiple data centers. 
>
> Thanks for letting me ask this here!