Oracle Coherence vs Riak

I have used Oracle Coherence Server and Riak database in the last 2 years and noted down the differences as below,

Oracle Coherence Riak
In Memory Data Grid High performance Key/Value data store. Its a No SQL database. Distributed data store which means the data gets distributed across multiple nodes
Its not a commercial version Apache license but also have a commercial version
In Coherence, we should have to create a cache, then we can store the data in key/value format In Riak, we should create a bucket similar like cache in coherence server, then we can store the data in key/value format
Supports API calls, Query and ReSt API calls. Supports Protobuf API calls and also provide ReSt API’s
The object to be stored is either a Java object or POF object[Portable object format] It can store json/binary data
We can use CohQL to interact with coherence cache[Its a light weight query language] We can use ReSt API to interact with Riak buckets