In this lesson you will learn how to update data, using values or conditions in another table. As with the INSERT statement, you will use the FROM clause in your statement.

In the previous lesson, we helped WSS track who was getting raises, and when. We did this by inserting values from WSS’s Employee table into their SalaryHistory table.
After tracking the SalaryHistory table for a few months, management has determined that employees are generally underpaid, and WSS is at risk of losing employees. WSS now plans to issue a raise of 10% to everyone who has not had a raise in the past 12 months.
Below are WSS's SalaryHistory and Employee tables.

To accomplish this, we must update the CurrentSalary column of the Employee table so that it becomes 1.1 times the value in the table currently for all employees who:

Because there will be more employees in the Employee table than are in the SalaryHistory table, performing a regular (inner) join will not produce the desired results. We need to construct an outer join to retrieve all data in the Employee table. The following Transact-SQL statement shows how to construct this UPDATE Transact-SQL statement.

Click the Exercise link below to practice updating data with values from another table.
In the next lesson, you will learn how to delete data using values from another table.
Updating Data Values - Exercise