ORDER BY, GROUP BY(~별로)
COUNT(*) AS 개수
숙제
SELECT payment_method ,count(*) from orders
WHERE email like '%naver.com' and course_title ='앱개발 종합반'
group by payment_method ORDER BY, GROUP BY(~별로)
COUNT(*) AS 개수
숙제
SELECT payment_method ,count(*) from orders
WHERE email like '%naver.com' and course_title ='앱개발 종합반'
group by payment_method 