Introduction to NoSQL Databases

NoSQL means Not only SQL. The term refers to a class of databases that are non-relational in architecture. They have their roots in the open source community. NoSQL databases have become more popular due to the demands of Big Data.

In this module, you will learn about the characteristics of NoSQL and the four main categories of NoSQL databases available. You will explore the differences between the ACID and BASE consistency models, the advantages and challenges of distributed systems, and the CAP theorem and its characteristics. You will learn how to decide when to use RDBMS and when to use NoSQL.

MongoDB is a document-oriented NoSQL database. It is easy to access by indexing and supports various data types, including dates and numbers. MongoDB is the most popular NoSQL database today, empowering users to query, manipulate, and find interesting insights from their collected data. It can also be used for a variety of purposes because of the flexibility of storing structured or unstructured data.

In this module, you will learn about the characteristics of MongoDB and expand your hands-on working knowledge of MongoDB performing various common tasks including create, read, update, and delete (CRUD) operations, limit and sort records, indexing, and aggregation. You will explore replication and sharding, which are very important concepts in MongoDB. The scale and availability we see with MongoDB is achieved using these two concepts.

Apache Cassandra is an open source database. It is best used by "always available" type of applications that require a database that is always available, that scales fast in situations of high traffic, and is the right choice when you need scalability and high availability without compromising performance. Apache Cassandra is best used by online services like Netflix, Uber, and Spotify.

In this module, you will learn about the characteristics of Apache Cassandra. You will also expand your hands-on working knowledge of Cassandra performing various common tasks including using the CQL shell, keyspace operations, table operations, and CRUD operations.

Database-as-a-service (DBaaS) is a popular solution for hybrid multicloud applications. IBM Cloudant is a fully managed DBaaS built on open source Apache CouchDB. Cloudant aims to be the data layer for all your web and mobile applications. In this module, you will find out how simple developing modern web applications is with Cloudant's rich features and JSON document store.​You will explore the architecture of Cloudant as a NoSQL database. You will gain hands-on experience with Cloudant capabilities and key technologies. And you will learn how to use the Cloudant dashboard to create and manage your database.