36. Comparing dates and datetimes

So far we’ve been using the signup_date column in the users table to filter data:

SELECT COUNT(*) FROM users WHERE signup_date BETWEEN '2018-01-01' AND '2018-01-07' 

As you remember, signup_date is simply a date when a user signed up (in other words, when a record in the users table was created). The signup timestamp is stored inside the created_at column which has type datetime. We can use the created_at column for our filter the same way:

SELECT COUNT(*) FROM users WHERE created_at BETWEEN '2018-01-01' AND '2018-01-07' 

SQL will figure out that...