Transactions background

MongoDB is a non-relational database and provides only a few guarantees around ACID. Data modeling in MongoDB does not focus on BCNF, 2NF, and 3NF normalization; instead, its focus is in the opposite direction.

In MongoDB, the best approach is often to embed our data into subdocuments, resulting in more self-contained documents than a single row of data in an RDBMS. This means that a logical transaction can affect a single document many times. Single-document transactions are ACID-compliant in MongoDB, meaning that multi-document ACID transactions have not been essential for MongoDB development.

However, there are a few reasons why getting multi-document transactions is a good idea. Over the years, MongoDB has grown from being a niche database to a multi-purpose database that is used everywhere – from start-ups to major Fortune 500 companies. Across many different use cases, there are inevitably a few corner cases where data modeling can’...