下面这个语句可以查找出 Bingren 表中 Pname 字段相同的数据 没有问题。
string Sql = "select * from Bingren where Pname in (select Pname from Bingren group by Pname having count(1) >= 2) “;
string Sql = "select * from Bingren where Pname in (select Pname from Bingren group by Pname having count(1) >= 2) AND Hs in (select Hs from Bingren group by Hs having count(1) >= 2)";