Gridview coading problem

Try this and change as per your requirement

create a stroed procedure as follows

createPROCEDURE insertData
(
@ID int,
@Name varchar(50),
@Address varchar(50)
)
as
begin
iF NOT EXISTS (
select * from Employee 
where EmployeeName = @Name AND Address = @Address) // here compare with your desired column 

insert into Employee(EmpID,EmployeeName,Address)values(@ID,@Name,@Address)
   
    END

from your code 
string constring = ConfigurationManager.ConnectionStrings["vendorConn"].ConnectionString;
SqlConnection sqlCon = new SqlConnection(constring);
           
            SqlCommand cmd = new SqlCommand("insertData",sqlCon);
            cmd.Parameters.AddWithValue("@ID", 2000);
            cmd.Parameters.AddWithValue("@Name", "Dorababu");
            cmd.Parameters.AddWithValue("@Address", "Hyderabad");
            cmd.CommandType = CommandType.StoredProcedure;
            sqlCon.Open();
            if (cmd.ExecuteNonQuery() > 0)

yes,and second thing is when i assign particular subject for particular lecturer timings will be different.Don't assign same timings for two lecturer.  

I am  sending  by designing page.