Instruction
Let's start with customer acquisition. We'll begin by counting how many new registrations occurred in a given period. By observing how the registration count changes over time, we'll be able to assess whether our promotional campaigns have worked or not.
We'll discuss the following reports:
- The number of registrations in the given period.
- The number of registrations in the current period of time (current week, current month, etc.).
- The number of registrations over time, tallying registrations in each month or in each week.
To count the number of registrations in 2016, we can use the following query:
SELECT COUNT(customer_id) AS registration_count_2016 FROM customers WHERE registration_date >= '2016-01-01' AND registration_date < '2017-01-01';
The query is quite simple. Just remember proper time filtering: use the 'yyyy-mm-dd' format (year, month, day) when you write the dates.
Exercise
How many customers registered in the first six months of 2017? Name the column registration_count.
Stuck? Here's a hint!
To get the first six months of 2017, use the following WHERE clause:
WHERE registration_date >= '2017-01-01' AND registration_date < '2017-07-01';




