London 9 - Andriana Saffo - SQL - Week 2

2-exercises/task.md

@@ -7,6 +7,7 @@ In this homework, you are going to work with an ecommerce database. In this data
 Below you will find a set of tasks for you to complete to set up a database for an e-commerce app.
 
 To submit this homework write the correct commands for each question here:
+
 ```sql
 
 
@@ -35,16 +36,92 @@ 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
+
+```sql
+ANSWER: SELECT name, address FROM customers WHERE country = 'United States';
+
+```
+
 2. Retrieve all the customers in ascending name sequence
+
+```sql
+ANSWER: SELECT * FROM customers ORDER BY name ASC;
+
+```
+
 3. Retrieve all the products whose name contains the word `socks`
+
+```sql
+ANSWER: 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.
+
+```sql
+ANSWER: SELECT pa.prod_id, p.product_name, pa.unit_price, pa.supp_id FROM products p Join product_availability pa ON (pa.prod_id = p.id) WHERE pa.unit_price > 100;
+
+```
+
 5. Retrieve the 5 most expensive products
+
+```sql
+ANSWER: SELECT * FROM products INNER JOIN product_availability ON prod_id = products.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`
+
+```sql
+ANSWER: SELECT p.product_name, pa.unit_price, s.supplier_name FROM products p INNER JOIN product_availability pa ON (pa.prod_id = p.id) INNER JOIN suppliers s ON (s.id = pa.supp_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`.
-8. Retrieve all orders, including order items, from customer ID `1`. Include order id, reference, date and total cost (calculated as quantity * unit price).
+
+```sql
+ANSWER: SELECT p.product_name, s.supplier_name FROM products p JOIN product_availability pa ON (pa.prod_id = p.id) JOIN suppliers s ON (s.id = pa.supp_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).
+
+```sql
+ANSWER: SELECT oi.order_id, o.order_reference, o.order_date, oi.quantity * pa.unit_price AS total_cost FROM orders o JOIN order_items oi ON (o.id = oi.order_id) JOIN product_availability pa ON (oi.id = pa.prod_id) WHERE o.customer_id = 1;
+
+```
+
 9. Retrieve all orders, including order items, from customer named `Hope Crosby`
+
+```sql
+ANSWER: SELECT o.*, oi.* FROM orders o JOIN order_items oi ON (o.id = oi.order_id) 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`.
+
+```sql
+ANSWER: SELECT p.product_name, pa.unit_price, oi.quantity FROM products p JOIN product_availability pa ON (pa.prod_id = p.id) JOIN order_items oi ON (pa.prod_id = oi.product_id) JOIN orders o ON (o.id = oi.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`.
+
+```sql
+ANSWER: SELECT c.name, o.order_reference, o.order_date, p.product_name, s.supplier_name, oi.quantity FROM customers c JOIN orders o ON (c.id = o.customer_id) JOIN order_items oi ON (o.id = oi.order_id) JOIN suppliers s ON (oi.supplier_id = s.id) JOIN products p ON (p.id = oi.product_id);
+
+```
+
 12. Retrieve the names of all customers who bought a product from a supplier based in China.
-13. List all orders giving customer name, order reference, order date and order total amount (quantity * unit price) in descending order of total.
 
+```sql
+ANSWER: SELECT DISTINCT c.name FROM customers c JOIN orders o ON (c.id = o.customer_id) JOIN order_items oi ON (oi.order_id = o.id) JOIN products p ON (oi.product_id = p.id) JOIN suppliers s ON (oi.supplier_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.
+
+```sql
+ANSWER: SELECT c.name, o.order_reference, o.order_date, oi.quantity * pa.unit_price AS total_amount FROM customers c JOIN orders o ON (c.id = o.customer_id) JOIN order_items oi ON (oi.order_id = o.id) JOIN product_availability pa ON (oi.product_id = pa.prod_id) ORDER BY total_amount DESC;
+
+```

3-projects/.gitignore

@@ -0,0 +1 @@
+node_modules