Planet NoSQL

  Introduction By any measure, MongoDB is a popular document-oriented JSON database. In the last dozen years, it has grown from its humble beginnings of a single lock per database to a modern multi-document transaction with snapshot isolation. MongoDB University has trained a large number of developers to develop the MongoDB database. There are many JSON databases now. While it's easy to start with MongoDB to learn NoSQL and flexible JSON schema, many customers choose Couchbase for performance, scale, and SQL. As you progress in your database evaluation and evolution, it's easier to start from what you know now. That's the idea for this series. Use your MongoDB knowledge to easily learn and eventually master Couchbase.  Don't despair if you don't know MongoDB do know any one of the RDBMS. This Oracle to Couchbase series will help you learn by comparison.  Many nations are known by their language: French, German, Spanish). Many databases are known for their language...

To database what Yoda is to Star Wars, optimizer is. - Yoda Separating the HOW (logical, physical representations, access methods) from WHAT (the SQL query) was the genius of the relational model. SQL has been unreasonably effective for relational model and beyond. A good optimizer is critical for SQL irrespective of the data model. The job of an optimizer is to produce an efficient execution algorithm, commonly known as the query plan or simply the plan.  Oracle is a RDBMS, used a rule based optimizer(RBO) for many years before  switching to Selinger style cost-based optimizer.  Couchbase N1QL is a declarative query language that is SQL for JSON. Couchbase N1QL also started with a rule based optimizer.  In 2021, we added a cost based optimizer (CBO) for the query service. CBO for the analytics service is on the roadmap.  JSON is flexible, supports complex objects, arrays in documents and predicates.   Couchbase's patented cost based optimizer builds o...