Problem
Example
Thinking
ํ ์ด๋ธ์์ ์ค๋ณต์ด ๋๋ ์ด๋ฉ์ผ์ ์ถ๋ ฅํด์ฃผ๋ฉด ๋๋ค.
์ค๋ณต๋ ์ด๋ฉ์ผ์ GROUP BY๋ก ๋ฌถ์ด์ฃผ๊ณ
HAVING์ ์ฌ์ฉํด์ count ๊ฐ์ด 1 ์ด๊ณผ (ํน์ 2 ์ด์)์ธ email ๊ฐ์ ๊ณจ๋ผ์ฃผ์
Solve
์ ์ถ ๋ต์
select email as Email from Person
GROUP BY email
HAVING COUNT(*) > 1;
https://leetcode.com/problems/duplicate-emails/submissions/
Duplicate Emails - LeetCode
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