DQL (Data Query Language)

Data Query Language (DQL) is a subset of SQL focused on retrieving data from a database without modifying it. The primary command in DQL is SELECT, which allows users to specify which columns to retrieve and from which table, optionally applying conditions for filtering results. DQL is essential for querying and extracting information from databases for various purposes, such as reporting and analysis. It provides powerful capabilities for searching, sorting, and aggregating data to meet specific requirements.

SELECT: The SELECT statement retrieves data from the table.

SELECT employee_id, first_name, last_name FROM employees WHERE department = 'Sales';

In this example, we're selecting the employee ID, first name, and last name of employees who work in the 'Sales' department from the 'employees' table. This query will return a list of employees' details who are part of the sales department.

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