Resolution of different questions about a SQL database. The questions:
- Select all the details of products priced over 100.
- Shows products that belong to category co ID 18 and have a weight of more than 1000.
- Select the names and prices of the products priced between 50 and 300.
- Shows how many products are in each category.
- Get the total amount of sales per customer.
- Displays customers who have purchased more than 10 products in total.
- Displays the name of the products together with the name of the category they belong to.
- Displays product names and dates of orders in which they have been sold.
- Displays product names and the names of customers who have purchased those products.
- Find the customers who have spent more than 1000, and how much they have spent.