code: public boolean execInsert(D6Model[] modelObjects, D6Inex includeExcludeColumnNames, boolean ignoreDuplicate) {
      log("#execInsert");
      boolean retVal = false;
  
      if (modelObjects == null) {
        return retVal;
      }
  
      final int numOfModelObjects = modelObjects.length;
  
      if (numOfModelObjects == 0) {
        return retVal;
      }
  
      final D6Model firstModelObject = modelObjects[0];
  
      final D6CrudInsertHelper d6CrudInsertHelper = new D6CrudInsertHelper(firstModelObject.getClass());
  
      final String insertSQL = d6CrudInsertHelper.createInsertPreparedSQLStatement(includeExcludeColumnNames, ignoreDuplicate);
  
      Connection conn = null;
  
      try {
  
        PreparedStatement preparedStmt = null;
  
        conn = createConnection();
  
        // There is a possibility that the error occurs in one single insert
        // statement.
        // Therefore, turn the auto commit off.
        conn.setAutoCommit(false);
  
        preparedStmt = conn.prepareStatement(insertSQL);
  
        for (int i = 0; i < modelObjects.length; i++) {
  
          D6Model model = modelObjects[i];
  
          d6CrudInsertHelper.map(model, preparedStmt, includeExcludeColumnNames);
  
          // execute SQL
          preparedStmt.executeUpdate();
  
        }
  
        // finally commit
        conn.commit();
  
        retVal = true;
  
      } catch (SQLException e) {
  
        loge("#execInsert", e);
        retVal = false;
  
      } catch (D6Exception e) {
  
        // catch from helper
        loge("#execInsert", e);
        retVal = false;
      } finally {
        if (conn != null) {
          try {
  
            conn.close();
          } catch (SQLException e) {
            loge("#execInsert", e);
            retVal = false;
          }
        }
      }
      return retVal;
  
    }
docs: Insert the specified model object into the DB
  
  @param modelObjects
  @param includeExcludeColumnNames
  You can select either 'the column name you want to reflected
  in the database' AND 'the column name you don't want to
  reflect in the database'. When omitted (null specified)
  ,reflects all properties in the model class has to be
  reflected to the database.
  @param ignoreDuplicate
  if ignore duplicated entry
  @return true:DB operation success false:failure