I am evaluating Mongo db versus Couch base for use in storing historical financial data. As far as query speed and aggregation(group, sum etc) is concerned Couch base wins by a significant margin.
When a large body of data exists (30 -40 millions documents in a bucket), creating an index on Couch Base takes much longer than Mongo db.
Perhaps i am missing something when I create indexes on Couch Base.
I use "CREATE INDEX ix9 ON bucket(… fields…) USING GSI
Is this the correct way to create a new index when data already exists?