首先，确定重复项。其次，重新加入以提取这些行。

非聚集（或非窗口/排名）自连接形成部分交叉连接，并为任何一组键给出重复的平方。也包括非重复项。毕竟1 x 1 = 1。

SELECT
    t2.*
FROM
    (
    SELECT 
       StateId, OrderId, OrderTime, PermitId
    FROM
       myTable
    GROUP BY
       StateId, OrderId, OrderTime, PermitId
    HAVING
       COUNT(*) >= 2
    ) T1
    JOIN
    mytable T2 ON T1.StateId = T2.StateId AND T1.OrderId = T2.OrderId AND
                   T1.OrderTime = T2.OrderTime AND T1.PermitId = T2.PermitId