求SQL语句可以查询2个字段的组合的不重复结果,注意是排列组合的...答:例:表名为T SQL语句为:SELECT t1.A AS A,t1.B AS B, t1.C+t2.C AS C FROM (SELECT * FROM (SELECT A, B, Sum(T.C) AS C FROM T GROUP BY T.A, T.B )AS t1,(SELECT A, B, Sum(T.C) AS C FROM T GROUP BY T.A, T.B )AS t2 WHERE t1.A=t2.B AND t1...