code: @Override
      protected void prepare(final AbstractSQLInsertUpdate<?> _insertUpdate,
                             final Attribute _attribute,
                             final Object... _values)
          throws SQLException
      {
          if (_insertUpdate instanceof SQLUpdate) {
              final long id = ((SQLUpdate) _insertUpdate).getIds()[0];
              final SQLSelect sel = new SQLSelect();
              sel.column(0, _attribute.getSqlColNames().get(0))
                  .from(_attribute.getTable().getSqlTable(), 0)
                  .addPart(SQLPart.WHERE)
                  .addColumnPart(0, "ID")
                  .addPart(SQLPart.EQUAL)
                  .addValuePart(id);
  
              ConnectionResource con = null;
              try {
                  con = Context.getThreadContext().getConnectionResource();
  
                  final Statement stmt = con.createStatement();
                  final ResultSet rs = stmt.executeQuery(sel.getSQL());
                  if (rs.next()) {
                      this.currentValue = rs.getString(1);
                  }
                  rs.close();
                  stmt.close();
              } catch (final EFapsException e) {
                  throw new SQLException(e);
              }
          }
          checkSQLColumnSize(_attribute, 1);
          _insertUpdate.column(_attribute.getSqlColNames().get(0), eval(_values));
      }
docs: {@inheritDoc}