Mongo DB app migration to Google Cloud Data store

[79r9s8 via StackOverflow]

Am from RDBMS/Java background and recently started with Mongo DB. I am wondering if a Mongo DB based java application is ported to GAE to use Google Cloud Storage i.e. Big Table, how much model change and code change may be required.

I understand each No SQL implementation have their own set of functionalities & data types, hence my question is around basic database functionalities like open , insert, update, find or delete. Will I require code change for such operations.

If application is modeled and developed using MongoDB using simple entities, what challenge we may face to port it on google cloud ?

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