Problem

Write a stored procedure that takes in two parameters, a start date and an end date, and returns the number of days between the two dates.
Example input:
start date: 2017-01-01
end date: 2017-01-31
Example output:
31

Solution

/*

Solution:

CREATE PROCEDURE get_days_between_dates(start_date DATE, end_date DATE)
BEGIN
  SELECT DATEDIFF(end_date, start_date) AS days_between;
END;

Explanation:

The DATEDIFF function is the most efficient way to calculate the number of days between two dates.

*/