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SqlCommand com = new SqlCommand("select * from myuser where username=@UserName and password=@Pwd", con);
com.Parameters.Add(new SqlParameter("@UserName", UserName));
com.Parameters.Add( new SqlParameter("@Pwd",Pwd));
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and rowid not i ......
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select orders.EmployeeID,Employees.EmployeeID
from orders INNER JOIN Employees
on Employees.EmployeeID=orders.EmployeeID
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