有一个称为数据库值的属性，您可以通过该属性检查字段是否已修改，如果尚未修改，则只需退出验证触发器即可.

There is a property called database value that let you check if the field has been modified and if it has not you just have to exit the validation trigger.

例如.

    BEGIN

    IF :BLOCK.ITEM = GET_ITEM_PROPERTY('BLOCK.ITEM', database_value) THEN
     RETURN;
    END IF;

     /* VALIDATION */

    END;