我有一个我正在尝试恢复的单个集合的现有 mongodump。运行 mongo restore 后，没有出现错误，并且数据不在集合中。是否有任何已知的原因会发生这种情况？我希望如果由于某种原因没有插入数据，日志中会出现错误。
为了创建并尝试恢复转储，我遵循了为这个问题提供的答案： How to use mongodump for 1 collection
我在另一台服务器上创建了一个新数据库，它有一个空集合。我检查了 mongo 日志文件，没有错误，它显示连接打开并进行身份验证，然后在下一行断开连接。
mongorestore -vvvvv -u user -p 'password' --db=MyDatabase --collection=MyCollection dump1/MyCollection.bson
2015-03-04T18:20:31.331+0000 creating new connection to:127.0.0.1:27017
2015-03-04T18:20:31.332+0000 [ConnectBG] BackgroundJob starting: ConnectBG
2015-03-04T18:20:31.332+0000 connected to server 127.0.0.1:27017 (127.0.0.1)
2015-03-04T18:20:31.332+0000 connected connection!
connected to: 127.0.0.1
2015-03-04T18:20:31.333+0000 drillDown: dump1/MyCollection.bson
2015-03-04T18:20:31.333+0000 dump1/MyCollection.bson
2015-03-04T18:20:31.333+0000 going into namespace [MyDatabase.MyCollection]
Restoring to MyDatabase.MyCollection without dropping. Restored data will be inserted without raising errors; check your server log
file size: 94876
130 objects found
2015-03-04T18:20:31.336+0000 Creating index: { key: { _id: 1 }, name: "_id_", ns: "MyDatabase.MyCollection" }
2015-03-04T18:20:31.340+0000 Creating index: { key: { geometry: "2dsphere" }, name: "geometry_2dsphere", ns: "MyDatabase.MyCollection", 2dsphereIndexVersion: 2 }
日志文件：
2015-03-04T18:20:31.333+0000 [conn874] authenticate db: MyDatabase { authenticate: 1, nonce: "xxx", user: "user", key: "xxx" }
2015-03-04T18:20:31.342+0000 [conn874] end connection 127.0.0.1:59420 (25 connections now open)
我在起点和终点上使用的查询是：
db.MyCollection.find()
在源服务器上，该集合有 130 个元素，这也显示在 mongorestore 输出“找到 130 个对象”中。
编辑：
我将--drop选项添加到 mongorestore 命令。日志文件输出清楚地表明它正在为空集合创建索引。
2015-03-20T15:03:57.565+0000 [conn61965] authenticate db: MyDatabase { authenticate: 1, nonce: "xxx", user: "user", key: "xxx" }
2015-03-20T15:03:57.566+0000 [conn61965] CMD: drop MyDatabase.MyCollection
2015-03-20T15:03:57.631+0000 [conn61965] build index on: MyDatabase.MyCollection properties: { v: 1, key: { _id: 1 }, name: "_id_", ns: "MyDatabase.MyCollection" }
2015-03-20T15:03:57.631+0000 [conn61965] added index to empty collection
2015-03-20T15:03:57.652+0000 [conn61965] build index on: MyDatabase.MyCollection properties: { v: 1, key: { geometry: "2dsphere" }, name: "geometry_2dsphere", ns: "MyDatabase.MyCollection", 2dsphereIndexVersion: 2 }
2015-03-20T15:03:57.652+0000 [conn61965] added index to empty collection
2015-03-20T15:03:57.654+0000 [conn61965] end connection 127.0.0.1:59456 (21 connections now open)