Relational database

A relational database is a structured system for storing and managing data in tables that are connected through relationships. It follows the relational model, where data is organized into rows and columns, making it easy to retrieve and manipulate using SQL (Structured Query Language).


Key Features of Relational Databases:

Tables (Relations): Data is stored in tables, each containing rows and columns.


Rows (Records/Tuples): Each row represents a single data entry.


Columns (Attributes/Fields): Each column stores a specific type of information.


Primary Key (PK): A unique identifier for each record in a table.


Foreign Key (FK): A reference to a primary key in another table, creating relationships.


SQL (Structured Query Language): The language used to query and manage the database.


Benefits of Using a Relational Database:

  •  Data Integrity & Accuracy: Enforces rules to maintain consistency.
  •  Efficient Data Retrieval: Supports complex queries and relationships.
  •  Scalability: Can handle large amounts of data.
  •  Security: Allows controlled access to data.


Popular Relational Database Systems (RDBMS):

MySQL

PostgreSQL

Microsoft SQL Server

Oracle Database

SQLite

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