Remember this engine is runningbackward, and we're pumping heat up.
记住这个热机是反向运行的，我们把热量向上传输。
2
Objects or attributes relating only to the new version will be lost after a backward migration, and therefore you should not backward migrate after running the new version for an extended period.
与新版本相关的对象和属性在向后迁移后将丢失，因此在运行新版本较长一段时间后最好不要进行向后迁移。
3
Remember this one's runningbackward, we're pumping heat up.