What is RDBMS (relational database management system)?

RDBMS (relational database management system /relational database management system) — is software that allows you to create, manage and interact with relational databases. In relational databases, information is organized into tables that consist of rows and columns. Each row in the table represents a separate record (or data row), and the columns contain properties or fields that characterize that record. The basis for RDBMS is a relational data model proposed by mathematician Edgar Codd in 1970.

The relational model is based on the concept that all data should be presented in the form of tables (also called relations or relations, but personally I have not encountered the use of these terms in living language). This allows you to store large amounts of information in a structured form, using relationships between tables. Connections are created using — keys, for example, using a primary key (a unique identifier for each record) and a foreign key (a reference to the primary key of another table).

One of the key features of RDBMS is support for the SQL (Structured Query Language) language. SQL is used for database queries, data manipulation (add, update, delete), and database structure management. For example, with SQL you can get a list of all students who have passed the exam, or update the addresses of all clients who have changed their city of residence.

If we talk about examples of RDBMS, the most famous systems are MySQL, PostgreSQL, Oracle Database and Microsoft SQL Server. All of them have their own characteristics, but work on the basis of the same relational data model.

The use of RDBMS is extremely useful when it comes to working with large amounts of data, maintaining relationships between different types of information, and ensuring its integrity and consistency. Thanks to relational databases, you can quickly search for the necessary information, easily change the data structure and maintain a high level of organization.

One of the key concepts in RDBMS is transactions. A transaction (atomic transaction) is a group of database operations that are executed as a single entity. This is important to ensure the reliability of the system, as it allows you to ensure that even in the event of an error, all changes will either be successfully completed or canceled.

In the image, I tried to depict the interaction scheme between RDBMS, SQL and tables

RDBMS <TAG1> is the framework that provides work with relational databases.

Tables in RDBMS, they contain columns (data attributes) and rows (individual records).

SQL <TAG1> is the language used to interact with RDBMS. It is used to perform requests to sample, insert, update and delete data, as well as to manage the structure of the database and access to it. We will talk about the Primary and Foreign keys in a separate post.