Business Analyst: What are SQL CTEs (Common Table Expressions)?

1WITH cte_name AS (
2  SELECT ...
3  FROM ...
4  WHERE ...
5)
6SELECT *
7FROM cte_name;

1WITH monthly_sales AS (
2  SELECT 
3    DATE_TRUNC('month', order_date) as month,
4    SUM(amount) as total
5  FROM orders
6  GROUP BY 1
7)
8SELECT 
9  month,
10  total,
11  LAG(total) OVER (ORDER BY month) as prev_month
12FROM monthly_sales;