Explain the solution you have written. For a given problem, come up with a SQL query. Can you explain how this SQL works?

When you write a SQL query you are essentially telling the database how to transform data from tables into a result set. A typical query has the following clauses:

1. SELECT – lists the columns or expressions you want in the output.
2. FROM – specifies the source tables and any joins between them.
3. WHERE – filters rows before any grouping or aggregation.
4. GROUP BY – aggregates rows that share the same values for the listed columns.
5. HAVING – filters groups after aggregation.
6. ORDER BY – sorts the final result.
7. LIMIT/OFFSET – restricts the number of rows returned.

For example, to find the top 5 products by sales you might write:

SELECT p.product_id,

   p.name,
   SUM(o.quantity * o.unit_price) AS total_sales

FROM orders o

JOIN products p ON o.product_id = p.product_id

GROUP BY p.product_id, p.name

ORDER BY total_sales DESC

LIMIT 5;

Here, the JOIN brings together order and product data. The GROUP BY aggregates sales per product. SUM calculates the total revenue. ORDER BY sorts the products from highest to lowest revenue, and LIMIT 5 keeps only the top five. Understanding each clause and how they interact lets you build complex queries that answer business questions efficiently.