The UPDATE command in SQL is a DML (Data Manipulation Language) command. Other DML commands are: INSERT and DELETE.
Example: Update a record in the Employee table
UPDATE Employee SET EmployeeLastName = 'Smith', City= 'New York' WHERE EmployeeID = 419031;
Output:Query OK, 1 row affected (0.01 sec)
Example: Update many record in the Customers table
The SQL command below will update any records in the Customers table who live in the state of Michigan with a telephone area code of 818. Their area code will be changed to 213.
UPDATE Customers SET AreaCode = 213 WHERE State = 'MI" AND AreaCode = 818
Output:Query OK, 1,102 row affected (0.01 sec)