What is SQL?

The SQL commands are categorized into smaller groups, namely:

• Data Definition Language (DDL): commands that define the structure of the database. For example, commands for creating or deleting tables;

• Data Query Language (DQL): commands that query, or in simpler terms, retrieve data from one or more tables;

• Data Manipulation Language (DML): commands that manipulate data within the existing tables. For example, commands for inserting, updating, or deleting rows.

Many everyday applications use Relational Databases to store data.

There are various implementations of SQL, which are mostly similar with some differences and additional features. This course will cover commands and syntax common to all popular SQL versions.

You will use SQL Server Management Studio (SSMS) for learning and practicing SQL. The next chapter will guide you through setting up SQL and SSMS on your machine.