GAE DataStore vs Google Cloud SQL for Enterprise Management Systems

Question

I am building an application that is an enterprise management system using gae. I have built several applications using gae and the datastore, but never one that will requir

Answer 1

From the Cloud SQL FAQ:

Should I use Google Cloud SQL or the App Engine Datastore?

This depends on the requirements of the application. Datastore provides NoSQL key-value > storage that is highly scalable, but does not support the complex queries offered by a SQL database. Cloud SQL supports complex queries and ACID transactions, but this means the database acts as a ‘fixed pipe’ and performance is less scalable. Many applications use both types of storage.

If you need a lot of writes (~XXX per/s) to db entity w/ distributed keys, that's where the Google App Engine datastore really shine.

If you need support for complex and random user crafted queries, that's where Google Cloud SQL is more convenient.