Not every company or application needs an elastic database. Some applications can get by just fine on a single database server, rendering database elasticity moot from their perspective. To make this determination, simply ask yourself:
1. Will I need more than a single database server? Look at your current load and your projected growth and ask yourself whether it will exceed the capacity of a single server. If it doesn’t now, nor will it in the future, then you don’t need an elastic database.
2. Will my load fluctuate sufficiently to warrant the investment in elasticity? If your database requirements won’t experience fluctuations in demand—e.g. daily, weekly, monthly, seasonal changes in the number of servers required—then elasticity isn’t important. For example, if you have a social networking application that requires 2 database nodes 24x7, but peaks at 10 nodes for 2 hours a night, then elasticity is important. If your …

The primary reasons people are moving to the public cloud are: (1) replace capital expenses with operating expenses (pay as you go); (2) use shared resources for processes like back-up, maintenance, networking (shared expenses); (3) use shared infrastructure that enables you to pay only for those resources you actually use, instead of consuming your maximum load resources at all times (pay-per-use). The first thing you’ll notice is that all 3 cloud benefits have their basis in finances or the cloud business model.
We will focus in on #3 above: Pay-Per-Use. The old school model was to build your compute infrastructure for the maximum load today, plus growth over the life-cycle of the equipment, plus some buffer so the systems don’t get overloaded from spikes in usage. The net result is that your average usage might run 10% of the potential for the infrastructure you mortgaged your home to buy. In other words, you were paying 10X more than …