Relational → NoSQL migration

A document database is not a faster relational database. It is a different set of trade-offs, and it pays off when the access pattern is known, the read shape is stable, and the joins you are doing today are the ones the model should have avoided. When that is not the case, the honest answer is an index and a schema change, and I will give you that answer.

When the move is right, the work is mostly modelling and migration mechanics: designing documents around how they are read, then getting the data across without a maintenance window.

What you get

• A read/write access pattern analysis before any schema is drawn
• A document model designed around queries, not around the old tables
• A dual-write or backfill migration path with verification at each stage
• The consistency and transaction assumptions written down, not discovered later