/** Add a clause where the ID is from an existing object. */ public <OD> Where<T, ID> idEq(Dao<OD, ?> dataDao, OD data) throws SQLException { if (idColumnName == null) { throw new SQLException("Object has no id column specified"); } addClause( new SimpleComparison( idColumnName, idFieldType, dataDao.extractId(data), SimpleComparison.EQUAL_TO_OPERATION)); return this; }