SqlConnection cn = new SqlConnection("Server=.;uid=sa;pwd=sa;database=你的数据库")
SqlCommand cmd = new SqlCommand("select count(*) as num from a,b", cn);
cn.Open();
if(Convert.ToInt32(cmd.ExecuteScalar().ToString())>0)
return true;
SqlCommand cmd = new SqlCommand("select count(*) as num from a,b", cn);
cn.Open();
if(Convert.ToInt32(cmd.ExecuteScalar().ToString())>0)
return true;
怎么写我也忘了
应该能解决你的问题
from
(select *
from a A left outer join b B
on A.aaa=B.bbb
unit
select *
from a A right outer join b B
on A.aaa=B.bbb
)