What is SQL?

SQL stands for Structured Query Language. It's the standard language used to access, manage, and manipulate data stored in relational databases. You can use SQL to retrieve information, insert new data, update existing records, or remove data you no longer need. Because SQL statements look a lot like ordinary English, it's straightforward to learn and remains one of the most popular ways to work with databases.

Why is SQL Important?

SQL is a key skill if you work with data. Data analysts and software developers use SQL to interact with databases. They can embed SQL queries inside programming languages like Java or Python to build applications that process data quickly. Almost every organization stores data in a relational database, so knowing SQL lets you query and transform that data in a clear and efficient way.

What Can SQL Do?

With SQL, you can perform a variety of tasks on your data:

• Run queries to search for data in a database.
• Retrieve information and filter it in useful ways.
• Insert new records into existing tables.
• Update existing data to keep it accurate.
• Delete information you no longer need.
• Create new databases and tables to store data.
• Define views and stored procedures for repeated tasks.
• Set permissions to control who can access or change data.

All these operations revolve around using SQL to organize and maintain data so you can keep it both consistent and accessible.

SQL as a Standard

SQL became a standard of the American National Standards Institute (ANSI) in 1986 and of the International Organization for Standardization (ISO) in 1987. In practice, different databases like Oracle, MySQL, or MS SQL Server have added their own extensions or unique features, but they all implement the core commands: SELECT, UPDATE, DELETE, INSERT, and WHERE.

A Brief History of SQL

SQL emerged in the 1970s, designed around the relational data model. It was originally called SEQUEL, short for “Structured English Query Language,” but was later shortened to SQL. Oracle, then called Relational Software, introduced the first commercial SQL-based database system.

Components of a SQL System

A typical SQL setup is part of a relational database management system (RDBMS). These systems arrange data in tables using rows and columns, and they link tables using relationships. Common RDBMS examples include MS SQL Server, SQLite, MySQL, and Postgres.

The main components of many relational database systems include:

• A server or instance that hosts your databases.
• Multiple databases that organize your data.
• Tables that store data in rows (records) and columns (attributes).
• Views that show custom snapshots of your data without altering the underlying tables.
• Stored procedures that allow you to automate and reuse logic on your data.
• Permissions that keep data secure.