title: I change a value in my application , but don't update in my database
body: <p>I write this code in my project but when I change a value in my application,appeared a exception and don't update my database,this code work for new but dont work for delete and edit data. </p>
  
  <p>CODE :</p>
  
  <pre><code>private void btnLecOk_Click(object sender, EventArgs e)
      {
              DataRow dr = (lecturesBindingSource.Current as DataRowView).Row;
              dr["Section_ID"] = Convert.ToInt32(cmbLec_Section_Name.SelectedValue);
              dr["Lecture_Type_ID"] = Convert.ToInt32(cmbLec_Lecture_Type.SelectedValue);
              dr["Practicable_Unit"] = numLec_Practicable_Unit.Value;
              dr["theoretical_Unit"] = numLec_Theoretical_Unit.Value;
              dr["Term"] = numLec_Term.Value;
  
              lecturesBindingSource.EndEdit();
              lecturesTableAdapter.Update(dsSchedule.Lectures);
              EnableLectureControls();
      }
  </code></pre>
  
  <p>Exception :</p>
  
  <blockquote>
    <p>System.Data.DBConcurrencyException was unhandled
    Message="Concurrency violation: the UpdateCommand affected 0 of the expected 1 records." Source="System.Data" RowCount=1</p>
  </blockquote>
  
  <p>Sql query foe update :</p>
  
  <blockquote>
    <p>UPDATE    Lectures
    SET              Lecture_Code = @Lecture_Code, Section_ID = @Section_ID, Lecture_Type_ID = @Lecture_Type_ID, Lecture_Name = @Lecture_Name, 
                          Practicable_Unit = @Practicable_Unit, theoretical_Unit = @theoretical_Unit, Lecture_Capacity = @Lecture_Capacity, Term = @Term
    WHERE     (Lecture_Code = @Original_Lecture_Code) AND (Section_ID = @Original_Section_ID) AND (Lecture_Type_ID = @Original_Lecture_Type_ID) AND 
                          (Lecture_Name = @Original_Lecture_Name) AND (Practicable_Unit = @Original_Practicable_Unit) AND (theoretical_Unit = @Original_theoretical_Unit) 
                          AND (Lecture_Capacity = @Original_Lecture_Capacity) AND (Term = @Original_Term)</p>
  </blockquote>