Today we learn a little bit of christmas magic. At this moment you already know all basic parts of the SQL and even JOIN clause. The more complex query become, the more options for solving problems we obtained. We want to find a christmas gift. We decided that we need something more valuable than Christmas tree. So, we need to display products that are more expensive than 'X-Mas Tree' product. The solution of this task is not uncommon, because the first thing we have to do is to know the price of 'X-Mas Tree', and then find all products with a price higher than the obtained number. With the help of SQL, the solution will look like two queries, at that, one query will be included in the other. The query inside another query is called subquery. In our case, subquery is to find the price of the 'X-Mas Tree':
SELECT price FROM products WHERE name LIKE 'X-Mas Tree'