code: @Override
      protected void prepare(final AbstractSQLInsertUpdate<?> _insertUpdate,
                             final Attribute _attribute,
                             final Object... _values)
          throws SQLException
      {
          checkSQLColumnSize(_attribute, 1);
          try {
              _insertUpdate.column(_attribute.getSqlColNames().get(0),
                                   Context.getThreadContext().getPerson().getId());
          } catch (final EFapsException e) {
              throw new SQLException("could not fetch current context person id", e);
          }
      }
docs: The instance method sets the value in the insert statement to the id of
  the current context user.
  
  @param _insertUpdate SQL insert / update statement
  @param _attribute    SQL update statement
  @param _values       new object value to set; values are localized and
  are coming from the user interface
  @throws SQLException on error