sql 如何查询只出现一次的数据

SELECT *

FROM 表A A

WHERE EXISTS (SELECT COUNT(*)

FROM 表A B

WHERE A.C = B.C

AND A.D = B.D

GROUP BY C, D

HAVING COUNT(*) = 1)

select * from 表名 where 姓名 in (select 姓名 from 表名 group by 姓名 having count(*)=1)

表名自己更换一下

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