Replace Query Data Save Help Me?

Question

 

 

 

 

if (msf.Text != "")

{

cmd = new SqlCommand("insert into tbl_sinking(CHARG) values(@charg)", sqlcon);

sqlcon.Open();

cmd.Parameters.AddWithValue("@charg", msf.Text);

cmd.ExecuteNonQuery();

sqlcon.Close();

MessageBox.Show("Record Inserted Successfully");

DisplayData();

ClearData();

}

else

{

MessageBox.Show("Please Provide Details!");

}

 

this query work 2 insert and replace value in same column  

 

1 column 10 value than replace any value replace  For Example 20  than replace to 10