Lesson 3.3
Combining Conditions with AND, OR & Parentheses
When a filter has multiple conditions, parentheses make your intent explicit.
AND and OR let one WHERE clause check more than one thing. Use AND when every condition must be true. Use OR when any condition can be true.
Parentheses matter when you mix them. They show which conditions belong together, the same way they do in arithmetic.
Pattern
select column_one, column_two
from table_name
where (condition_a or condition_b)
and condition_cSchema · Garden ShopTable · products9 columns · 24 rows
Table · products
9 columns · 24 rowsOne row per product, with price, cost, and inventory levels.
product_id intproduct_name textcategory_id intsupplier_id intprice decimalcost decimalquantity_on_hand intreorder_level intdiscontinued bool
Your task
Show each product's product name, price, and quantity on hand when the product costs more than$20 or has fewer than 10 units on hand. Exclude discontinued products.
SQL Workbench
⌘↵ to run·
Expected answer
- Columns: product_name, price, quantity_on_hand.
- Rows: 11 products.
- No discontinued products should appear.