"insert or replace into items(url,title,author,published,tags,content,raw) values(?,?,?,?,?,?,?)",
This heuristic can be illustrated by the following design. Let’s say we have an application that generates a report, compresses it with zip, and saves it to the disk. With this heuristic in mind, we wouldn’t want the report generation to depend on the zip algorithm. A change from zip to LZMA algorithm shouldn’t affect the report generation. Likewise, the compression module shouldn’t depend on the file storage module. If we follow that heuristic, we will be able to change file storage to network storage without affecting compression or the report module. (By the way, this design might not be ideal, for instance, these tasks are too small to be modules, but I hope it conveys the meaning of this heuristic).
，这一点在PDF资料中也有详细论述
Варвара Кошечкина (редактор отдела оперативной информации)
Фото: Kacper Pempel / Reuters