code: public T addTableColumn(final Connection _con,
                              final String _tableName,
                              final String _columnName,
                              final ColumnType _columnType,
                              final String _defaultValue,
                              final int _length,
                              final int _scale)
          throws SQLException
      {
          // CHECKSTYLE:ON
          final StringBuilder cmd = new StringBuilder();
          cmd.append("alter table ").append(getTableQuote()).append(_tableName).append(getTableQuote()).append(' ')
                          .append("add ").append(getColumnQuote()).append(_columnName).append(getColumnQuote())
                          .append(' ')
                          .append(getWriteSQLTypeName(_columnType));
          if (_length > 0) {
              cmd.append("(").append(_length);
              if (_scale > 0) {
                  cmd.append(",").append(_scale);
              }
              cmd.append(")");
          }
          if (_defaultValue != null) {
              cmd.append(" default ").append(_defaultValue);
          }
  
          AbstractDatabase.LOG.debug("    ..SQL> " + cmd.toString());
  
          final Statement stmt = _con.createStatement();
          try {
              stmt.execute(cmd.toString());
          } finally {
              stmt.close();
          }
  
          @SuppressWarnings("unchecked")
          final T ret = (T) this;
          return ret;
      }
docs: CHECKSTYLE:OFF