select distinct
이 자료 참고하기 (distinct 사용시 유의점)
https://blog.naver.com/PostView.naver?blogId=owl6615&logNo=222193523575&redirect=Dlog&widgetTypeCall=true&topReferer=https%3A%2F%2Fsearch.naver.com%2Fsearch.naver%3Fsm%3Dtab_hty.top%26where%3Dnexearch%26query%3Dsql%2Bdistinct%26oquery%3D%25ED%258C%258C%25ED%258C%258C%25EA%25B3%25A0%26tqi%3Dhjh9qlp0Jywss7%252BdWuZssssstKZ-245290&directAccess=false
❗️ distinct : 중복은 카운팅 안된다!
참고자료
https://www.w3schools.com/sql/exercise.asp?filename=exercise_where2
의미없는 삽질은 없다1