# Manifest
+ Atomic updates to database metadata
+ For example:
  
| Initial State | `Flush`                | `Compaction`    | Add New Column  |
| :------------ | :--------------------- | :-------------- | :-------------- |
| Add `file 1`  | Add `file 9`           | Add `file 10`   | family "system" |
| Add `file 2`  | Mark `log 6` persisted | Add `file 11`   |                 |
| Add `file 3`  |                        | Remove `file 9` |                 |
| Add `file 4`  |                        | Remove `file 8` |                 |
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After the `RocksDB` process crashes, during the reboot process, it will first read the contents of the manifest file, rebuild the `LSM` tree in memory, and then recover the contents of the `memtable` according to the `WAL` log.