Manchester - NW5 - Fatih Celebi - SQL - WEEK_2

2-exercises/task.md

@@ -35,16 +35,125 @@ Open the file `cyf_ecommerce.sql` in VSCode and examine the SQL code. Take a pie
 Once you understand the database that you are going to work with, solve the following challenge by writing SQL queries using everything you learned about SQL:
 
 1. Retrieve all the customers' names and addresses who live in the United States
+
+select name, address from customers
+where country like 'USA'
+
 2. Retrieve all the customers in ascending name sequence
+
+select * from customers
+order by name;
+
 3. Retrieve all the products whose name contains the word `socks`
+
+select * from products 
+where product_name like '%socks%'
+
 4. Retrieve all the products which cost more than 100 showing product id, name, unit price and supplier id.
+
+select p.id, p.product_name, pa.unit_price, pa.supp_id 
+from products p 
+inner join product_availability pa 
+on (p.id=pa.prod_id) 
+where pa.unit_price >100;
+
 5. Retrieve the 5 most expensive products
+
+ select p.product_name, pa.unit_price
+ from products p 
+ inner join product_availability pa
+ on p.id = pa.prod_id
+ order by unit_price desc
+ limit 5;
+
 6. Retrieve all the products with their corresponding suppliers. The result should only contain the columns `product_name`, `unit_price` and `supplier_name`
+
+ select p.product_name, pa.unit_price, s.supplier_name 
+ from products p 
+ inner join product_availability pa
+ on p.id = pa.prod_id
+ inner join suppliers s 
+ on pa.supp_id = s.id;
+
 7. Retrieve all the products sold by suppliers based in the United Kingdom. The result should only contain the columns `product_name` and `supplier_name`.
+
+select p.product_name, s.supplier_name 
+ from products p 
+ inner join product_availability pa
+ on p.id = pa.prod_id
+ inner join suppliers s 
+ on pa.supp_id = s.id
+ where s.country = 'United Kingdom';
+ . 
 8. Retrieve all orders, including order items, from customer ID `1`. Include order id, reference, date and total cost (calculated as quantity * unit price).
+
+select o_i.order_id, o.order_reference, o.order_date, o_i.quantity * p_a.unit_price as total_cost
+ from order_items o_i
+ inner join orders o
+ on o.id = o_i.order_id
+ inner join product_availability p_a
+ on o_i.product_id = p_a.prod_id
+ where o.customer_id = 1;
+
 9. Retrieve all orders, including order items, from customer named `Hope Crosby`
+
+select o.*, o_i.*
+ from order_items o_i
+ inner join orders o 
+ on o_i.order_id = o.id
+ inner join customers c
+ on o.customer_id = c.id
+ where c.name = 'Hope Crosby';
+
 10. Retrieve all the products in the order `ORD006`. The result should only contain the columns `product_name`, `unit_price` and `quantity`.
+
+ select p.product_name, p_a.unit_price, o_i.quantity
+ from order_items o_i
+ inner join products p 
+ on o_i.product_id = p.id
+ inner join product_availability p_a
+ on o_i.product_id = p_a.prod_id
+ inner join orders o 
+ on o.id = o_i.order_id
+ where o.order_reference = 'ORD006';
+
+
 11. Retrieve all the products with their supplier for all orders of all customers. The result should only contain the columns `name` (from customer), `order_reference`, `order_date`, `product_name`, `supplier_name` and `quantity`.
+
+ select c.name, o.order_reference, o.order_date, p.product_name, s.supplier_name, o_i.quantity
+ from customers c
+ inner join orders o 
+ on c.id = o.id
+ inner join order_items o_i
+ on o_i.order_id = o.id
+ inner join products p 
+ on o_i.product_id = p.id
+ inner join suppliers s
+ on o_i.supplier_id = s.id
+
 12. Retrieve the names of all customers who bought a product from a supplier based in China.
+
+ select distinct c.name
+ from customers c
+ inner join orders o 
+ on c.id = o.customer_id
+ inner join order_items o_i
+ on o.id = o_i.order_id
+ inner join product_availability p_a 
+ on o_i.product_id = p_a.prod_id
+ inner join suppliers s
+ on p_a.supp_id = s.id
+ where s.country = 'China';
+
 13. List all orders giving customer name, order reference, order date and order total amount (quantity * unit price) in descending order of total.
 
+ select distinct c.name, o.order_reference, o.order_date, o_i.quantity * p_a.unit_price as total_amount 
+ from customers c
+ inner join orders o 
+ on c.id = o.customer_id
+ inner join order_items o_i
+ on o.id = o_i.order_id
+ inner join product_availability p_a 
+ on o_i.product_id = p_a.prod_id
+ order by total_amount desc;
+