A relational database is a set of formally described tables from which data can be accessed or reassembled in many different ways without having to reorganize the database tables. The standard user and application programming interface (API) of a relational database is the Structured Query Language (SQL). SQL statements are used both for interactive queries for information from a relational database and for gathering data for reports.
There are a number of database categories, from basic flat files that aren't relational to NoSQL to newer graph databases that are considered even more relational than standard relational databases.
The main advantages of relational databases are that they enable users to easily categorize and store data that can later be queried and filtered to extract specific information for reports. Relational databases are also easy to extend and aren't reliant on physical organization. After the original database creation, a new data category can be added without all existing applications being modified.
Best Relational Database
Oracle MySQL
Finalists
MariaDB
Amazon RDS