Dear all,   my question is , i tried to refresh the data block using default where clause and then run execute_query. then the data vanished from the datablock. i can't imagine what has happen here ?   WKString := 'X_BLOCK.SEQ_NO = '||''''||WKOldPolSeq||''''; GO_BLOCK('X_BLOCK'); SET_BLOCK_PROPERTY('X_BLOCK',Default_Where,WKString); EXECUTE_QUERY();  -- when this stage data got vanished. is EXECUTE_QUERY is not working properly in 12C form?? or DEFAULT_WHERE issue??