[데이터분석] 코드카타 99

99. Number of Unique Subjects Taught by Each Teacher

 

https://leetcode.com/problems/number-of-unique-subjects-taught-by-each-teacher/description/

 

Write a solution to calculate the number of unique subjects each teacher teaches in the university.

Return the result table in any order.

 

중복되지 않은 과목수 찾기. 

(정답) 엇..그냥 했는데 됐다

select teacher_id,

           count(distinct subject_id) cnt

from Teacher

group by 1