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DML (Data Manipulation Language)

DML, or Data Manipulation Language, is a subset of SQL used for managing and manipulating data within a database. It includes commands like INSERT, UPDATE, DELETE, and SELECT. INSERT adds new records, UPDATE modifies existing ones, and DELETE removes records. SELECT retrieves data based on specified criteria. DML commands are essential for interacting with and modifying the contents of database tables.

INSERT: Adds new records into a table.

INSERT INTO employees (id, name, department, salary) VALUES (1, 'John Doe', 'Sales', 50000);

In this example, we're inserting a new employee named 'John Doe' into the 'employees' table with an ID of 1, belonging to the 'Sales' department, and having a salary of $50,000.

 

UPDATE: Modifies existing records in a table.

UPDATE employees SET salary = 55000 WHERE id = 1;

In this example, we're updating the salary of the employee with ID 1 in the 'employees' table to $55,000.

 

DELETE: Removes records from a table.

DELETE FROM employees WHERE id = 1;

In this example, we're deleting the employee with ID 1 from the 'employees' table. 

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