mongodb 归档格式是什么？

我已经使用它们的存档选项备份了一些 mongoDB，但我不能简单地解压它们。当我执行一些步骤来解压缩数据时，存档看起来像是一个大文件中的整个数据库。 我想获取各个收藏的文件。 有没有办法做到这一点？

$ tar -xvf valk.archive
tar: Unrecognized archive format
tar: Error exit delayed from previous errors.
$ file valk.archive
valk.archive: gzip compressed data, original size 13953183
$ gunzip valk.archive
gunzip: valk.archive: unknown suffix -- ignored
$ unzip valk.archive
Archive:  valk.archive
  End-of-central-directory signature not found.  Either this file is not
  a zipfile, or it constitutes one disk of a multi-part archive.  In the
  latter case the central directory and zipfile comment will be found on
  the last disk(s) of this archive.
unzip:  cannot find zipfile directory in one of valk.archive or
        valk.archive.zip, and cannot find valk.archive.ZIP, period.
$ mv valk.zip valk.gz
$ gunzip valk.gz
$ open .
$ tar -xvf valk
tar: Unrecognized archive format
tar: Error exit delayed from previous errors.
$ head valk
TemplateDatametadata�{"options":{},"indexes":[{"v":2,"key":{"_id":1},"name":"_id_","ns":"valk.TemplateData"}],"uuid":"f52402b5aba24856b072d57cc3e46a72"}size-dbvalkcollectioMetricsmetadata�{"options":{"capped":true,"size":10485760,"max":1000000},"indexes":[{"v":2,"key":{"_id":1},"name":"_id_","ns":"valk.Metrics"},{"v":2,"key":{"openid":1},"name":"openid_1","ns":"valk.Metrics"}],"uuid":"43d92ff01815432c95dac5a2e05a64c0"}size�dbvalkcollection
AppConfigmetadata�{"options":{},"indexes":[{"v":2,"key":{"_id":1},"name":"_id_","ns":"valk.AppConfig"}],"uuid":"df633b0a43184de38e8b8ea7489cda3e"}size�dbvalkcollecMinibotZonesmetadata�{"options":{},"indexes":[{"v":2,"key":{"_id":1},"name":"_id_","ns":"valk.MinibotZones"}],"uuid":"095bbac0d17640be9e27dffe681b7d83"}size�dbvalkcollection    ChatLogsmetadataQ{"options":{"capped":true,"size":104857600,"max":10000000},"indexes":[{"v":2,"key":{"_id":1},"name":"_id_","ns":"valk.ChatLogs"},{"v":2,"key":{"openid":1,"createdAt":1},"name":"openid_1_createdAt_1","ns":"valk.ChatLogs"},{"v":2,"key":{"createdAt":1},"name":"createdAt_1","ns":"valk.ChatLogs"}],"uuid":"70586c82b3ae42cf8d9c47ad339ea55b"}size�dbvalkcollection

The mongodump归档格式是一种特殊用途的格式；你需要使用mongorestore --archive以及任何其他合适的选项。

例如，您可以使用--nsInclude选项 （mongorestore3.4+) 按命名空间有选择地恢复多个集合。

有关 MongoDB 存档格式的更多信息（以及原因）tar不适合），请参阅：MongoDB 工具中的归档和压缩。其要点是：

通用归档格式（例如 tar）仅支持归档中的连续文件打包。对 mongodump 和 mongorestore 使用这些存档格式将导致不可接受的性能下降，因为必须按顺序写入和读取所有集合中的数据。为了支持这些工具的并发行为，我们开发了一种支持非连续文件写入的特殊用途存档格式。新的归档功能大大提高了备份和恢复操作的效率。