What is a Relational Database?
How does one store and organize sets of data on a computer? The traditional way to store related pieces of data on a computer is via a relational database. A relational database is composed of one or more tables, each with columns, and corresponding fields. Each row is known as a record. For instance, if your columns were First Name, Last Name, and Age, a singular record might be Bob Jones 48.
The quality that these tables contain that makes them “relational” databases is a unique field (or combination of fields) in each, a key, which can then be referenced by another table. One or more records in a table can be related to one or multiple records in other tables, which means we can have various, functional dependencies, classified as one to one, one to many or many to many. By design, tables can easily be searched, organized, and have reports drawn from them. Relational databases uses Structured Query Language (SQL), a standard interface to perform operations and queries on the data within a relational database.
A relational database is able to perform operations like “select” for data retrieval, “project” for identifying data attributes and “join” for combining relations. Using SQL, users can easily create completely new tables from information stored in existing tables.