Yes, we did had to invest on new servers. Not only we need more RAM, we also needed more storage (which as expensive because we use SSDs). All things considered, SQL Server licences are not cheap either (6K-7K each) so in the long run I believe we will be saving money.
Our training was very much hands on: (1) we migrated a piece of code, (2) tested against a full-sized database, (3) profiled performance under load, (4) learned from the results, moved on the next piece of code (1).
Our plan if MongoDB wasn't good enough consisted basically of: (1) crying ourselves to sleep, (2) drinking heavily, and (3) contributing to MongoDB's development to make it good enough.
Our training was very much hands on: (1) we migrated a piece of code, (2) tested against a full-sized database, (3) profiled performance under load, (4) learned from the results, moved on the next piece of code (1).
Our plan if MongoDB wasn't good enough consisted basically of: (1) crying ourselves to sleep, (2) drinking heavily, and (3) contributing to MongoDB's development to make it good enough.