Following these rules:
- v1.5.0 and v1.6.0 can be used on top of the same files without any concerns, as their major version is the same, therefore the data format on disk is compatible.
- v1.6.0 and v2.0.0 are data incompatible as their major version implies, so files created with v1.6.0 will need to be converted into the new format before they can be used by v2.0.0.
- v2.x.x and v3.x.x are data incompatible as their major version implies, so files created with v2.x.x will need to be converted into the new format before they can be used by v3.0.0.
这个dgraph-io下的badger的新版本号tag已经到4.5了，pingcap下的badger看tag只有1.5。估计就是那个时候fork过来的。
这个引擎动不动就和以前的存储格式不兼容，升级的时候需要转换才能继续用。怕是难有人敢用啊。
而且unistore感觉就类似存算一体了。初期可能少用一些机器，长期看，存算不能独立伸缩是挺难受的。