Re: Can someone please explain me

[Peter Brawley]

It'd be more clear if it were written as ...

SELECT p.customer_id, sum(p_ammount) s, count(customer_id) N
FROM payment AS p
WHERE DATE(p.payment_date) BETWEEN last_month_start AND last_month_end
GROUP BY customer_id
HAVING s > min_dollar_amount_purchased and n > min_monthly_purchases;