Introduction to SQL
Learn about SQL, the standard language for relational database management.
What is SQL?
SQL (Structured Query Language) is a standardized programming language used to manage and manipulate relational databases. SQL is essential for performing tasks such as querying data, inserting records, updating data, and deleting data within a database.
- Standardized Language
- Efficient Data Querying
- Scalable for all application sizes
- Ensures Data Integrity
History of SQL
SQL was developed in the early 1970s by IBM, originally called SEQUEL. It became SQL and is now a standard endorsed by ISO and ANSI, widely used across relational databases worldwide.
Types of SQL Databases
Different database management systems support SQL, each with its own features. Below are a few of the most popular ones:
MySQL
An open-source database system widely used in web development.
PostgreSQL
An advanced open-source database system with extensive features.
SQLite
A serverless database system used in smaller applications and mobile devices.
Microsoft SQL Server
A commercial database system often used in enterprise applications.
SQL vs NoSQL
SQL is used for structured, relational data, while NoSQL is commonly used for unstructured or semi-structured data in applications requiring flexibility and scalability.
| Feature | SQL | NoSQL |
|---|---|---|
| Schema | Structured (Tables) | Flexible (Documents, Key-Value) |
| Query Language | SQL | No specific language |
| Use Case | Enterprise, E-commerce | Big Data, Real-time apps |
| Scalability | Vertical scaling | Horizontal scaling |