This advanced SQL exercise is part of the book: Advanced SQL – Practical Techniques and Use-Cases, which includes 100 day-to-day SQL challenges (and solutions), need-to-know advanced features, and key concepts.
An online education company manages a table that holds the details of the company’s customers. Each row in this table specifies: Serial number, customer name, city, and the date the customer joined the company.
CREATE TABLE customers (c_id int identity(1,1), c_name varchar(25), city varchar(25), join_date date) GO