Bluemix is IBM’s Platform-as-a-Service cloud. It is based on CloudFoundry and OpenStack and hosted in SoftLayer, primarily in Dallas, expanded to London and moving into Asia-Pacific. The catalog of services is constantly expanding. I’ve summarized those services related to storing data, a core requirement of any application. To address all the tire-kickers out there I’ve focused on what you can get for free.
MongoLab is a third party service that hosts various versions of MongoDB, either single instance or clustered. You can choose to run your service on AWS, Azure or Google Cloud. Billing is separate from Bluemix. A free sandbox is offered with 500MB of storage. Only the free/sandbox plan can be chosen from Bluemix, however, I believe that can be upgraded from the MongoLab site.
MongoDB by Compose. Compose (formerly MongoHQ) was acquired by IBM in July 2015. Among other DBaaS services it offers MongoDB. You can choose to host MongoDB on AWS, DigitalOcean or SoftLayer (acquired by IBM in July 2013 and the basis of Bluemix). Accounts and billing are not (yet?) integrated with Bluemix. Only a 30 day free trial exists, no free tier.
Cloudant was acquired by IBM in January 2014. It is a CouchDB compatible NoSQL database. The free tier is a generous 20GB. Unlike MongoDB which can also be installed and run locally, Cloudant is delivered as a full service DBaaS and can be hosted at SoftLayer, Rackspace and Azure with SoftLayer and Rackspace offering bare-metal options. Cloudant Local is an option to host the DBaaS behind your own firewall or setup yourself in a public cloud. Probably more involved and expensive than a lone developer wants to get. Cloudant offers shared and dedicated instances and a 30 day free trial. However if monthly costs are under $50 USD it’s free.
For relational databases options include MySQL, PostgreSQL, DB2 and Informix. Admittedly Informix does have some functional overlap with the NoSQL camp (supports JSON collections and MongoDB drivers), but it is still an RDBMS.
ClearDB is a third-party MySQL (5.5) relational database. Dedicated instances can be hosted on AWS or Azure. Multi-tenant plans are hosted on Azure, Pivotal.io, AppFog and Heroku. It is also possible to obtain MySQL in a VM that you host locally, but replicates out (master-master) to a dedicated cloud instance. The free tier offers a 5MB shared-instance database.
PostgreSQL by Compose. Accounts and billing are not integrated with Bluemix (although company was recently acquired by IBM). Only a 30 day free trial exists, no free tier. Curiously, compose.io, an IBM company, only hosts PostgreSQL on AWS where as ElephantSQL, a third-party, supports PostgreSQL on SoftLayer. *awkward*
SQL Database is a full service hosted DB2 database. The free tier allows up to 100MB.
This special purpose time series database is Informix under the covers. It also has NoSQL capabilities and seems to have a strong use case for Internet of Things applications. The first 1GB is free, but there is a charge per instance, so not quite sure how that works out.
All plans are a fully private, dedicated instance of DB2 (Workgroup Server Edition to Advanced Enterprise Server Edition) hosted on SoftLayer. There is nothing close to a free tier with this service. Look to the SQL Database service for that.
Box is a third-party that offers cloud based storage for generic files. The free tier offers 10GB with a 250MB file maximum. Unlike Dropbox that utilizes AWS-S3, Box is hosted on private data centers (though AWS is used for admin/non-production work).
Object Storage provides access to an OpenStack Swift object storage account (OpenStack is the foundation for Bluemix). The free tier offers 5GB.