Calculated updates
- SQL course
- Beginner
- Lesson 80/115
- 4 min
Update based on the current value.
Calculated update
You can use a calculation in SET. You can use the old column value in the new value.
UPDATE products
SET price = price * 1.10
WHERE category = 'kitap';This query raises prices of all books by 10%.
In products, price = price * 1.10 is updated. Only the rows where category = 'kitap' holds are affected.
Calculated update — details
SET price = price * 1.10 takes the old price, multiplies by 1.10 and writes it back. Ideal for bulk price changes.
Practice Calculated update
Raise all prices in products by 10%.
Starter code
-- raise prices
UPDATE products
SET price = priceSample solution
UPDATE products
SET price = price * 1.10Expected output
5 satır güncellendi
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What does SET price = price * 1.10 do?
- Sets the price to 10
- Resets the price to 0
- Increases the price by 10% Correct answer
- Halves the price
Explanation: multiplies the old price by 1.10.
2 Raise price
Question
UPDATE products
SET price = price ____ 1.10
WHERE category = 'kitap';
Answer
UPDATE products
SET price = price * 1.10
WHERE category = 'kitap';Explanation: price * 1.10 raises the price by 10%; the new value is computed from the old one.
3 Calculated updates: match the terms
| Term | Meaning |
|---|---|
UPDATE |
update |
SET |
new value |
* |
multiply |
WHERE |
condition |