There is a big concern regarding a recently-disclosed Rails SQL injection vulnerability. I am not well-versed in dealing with security, so I am unnerved. I hear that MongoDB is not susceptible to this kind of attack.
Is this a good reason to move to MongoDB permanently?
No. Just because SQL databases are vulnerable to SQL injection attacks is not a good reason to move to MongoDB.
MongoDB is great in certain use-cases, particularly where you need schema-less collections.
If you need to store relational data, you’ll be much better served by a relational DB.
In short, if you’re afraid of SQL injection, learn how to sanitize your inputs. Don’t move to MongoDB.
The newly found vulnerability does not affect everyone. Read here for more details.