Chapter 8. Working with Databases

If you work with data, sooner or later, you will come into contact with databases. This chapter introduces various databases (relational and NoSQL) and related APIs. A relational database is a database that has a collection of tables containing data organized by the relations between data items. A relationship can be set up between each row in the table and a row in another table. A relational database does not just pertain to relationships between tables; firstly, it has to do with the relationship between columns inside a table (obviously, columns within a table have to be related, for instance, a name column and an address column in a customer table); secondly, it relates to connections between tables.

NoSQL (Not Only SQL) databases are undergoing substantial growth in Big Data and web applications. NoSQL systems may in fact permit SQL-like query languages to be employed. The main theme of NoSQL databases is allowing data to be stored in a more flexible...