Introduction
INSERT with SELECT
Referring to other tables
INSERT, UPDATE and DELETE with JOIN
11. Update data using JOIN
INSERT, UPDATE, and DELETE with subqueries
Summary

## Instruction

Very well done!

As you probably guessed, JOIN is also used in UPDATE queries. Its usage is quite similar to how we used it in the INSERT INTO statement. Look at the query below, which decreases the price of a product if the order amount is more than 1000:

UPDATE Purchase
SET Purchase.TotalPrice = Product.Price * 0.75 * Purchase.Quantity
FROM Purchase
JOIN Product ON Purchase.ProductId = Product.Id
WHERE Purchase.TotalPrice > 1000;
We have to use the referenced table, Product, to get the price of the product; that's why we used JOIN in the SELECT clause.

## Exercise

Decrease the value of ordered products (Purchase table) by 15% if the product's TotalPrice (Product table) exceeds 10.

### Stuck? Here's a hint!

Use:

SET Purchase.TotalPrice = Product.Price * 0.85 * Purchase.Quantity