shardingState（数据库命令）

shardingState: shardingState is an admin command that reports if mongod is a member of a sharded cluster. To run the command, you must run against the admin database. See db.adminCommand().

兼容性

此命令可用于以下环境中托管的部署：

MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud

注意

This command is supported in all MongoDB Atlas clusters. For information on Atlas support for all commands, see Unsupported Commands.

MongoDB Enterprise：基于订阅、自我管理的 MongoDB 版本
MongoDB Community：源代码可用、免费使用且可自行管理的 MongoDB 版本

语法

该命令具有以下语法：

db.adminCommand(
  {
    shardingState: 1
  }
)

行为

For shardingState to detect that a mongod is a member of a sharded cluster, the mongod must satisfy the following conditions:

mongod是副本集的主节点，并且
mongod实例是分片集群的成员。

If shardingState detects that a mongod is a member of a sharded cluster, shardingState returns a document that resembles the following prototype:

{
  "enabled" : true,
  "configServer" : "<configdb-string>",
  "shardName" : "<string>",
  "shardHost" : "string:",
  "versions" : {
    "<database>.<collection>" : {
      "placementVersion": Timestamp({ t: 1, i: 1024 }),
      "timestamp": Timestamp({ t: 1682444810, i: 8 })
    },
    "<database>.<collection>" : {
      "placementVersion": Timestamp({ t: 0, i: 0 }),
      "timestamp": Timestamp({ t: 0, i: 0 })
    }
  },
  "ok" : 1,
  "$clusterTime" : {
     "clusterTime" : Timestamp({ t: 1682457265, i: 1 }),
     "signature" : {
        "hash" : BinData(0,"B2ViX7XLzFLS5Fl9XEuFXbwKIM4="),
        "keyId" : Long("6488045157173166092")
     }
  },
  "operationTime" : Timestamp({ t: 1682457260, i: 1 })
}

Otherwise, shardingState will return the following document:

{
  "enabled" : false,
  "ok" : 1,
  "$clusterTime" : {
     "clusterTime" : Timestamp({t:1510716515, i: 1}),
     "signature" : {
        "hash" : BinData(0,"B2ViX7XLzFLS5Fl9XEuFXbwKIM4="),
        "keyId" : Long("6488045157173166092")
     }
  },
  "operationTime" : Timestamp({t: 1510716515, i: 1})
}

The response from shardingState when used with a config server is:

{
   "enabled" : false,
   "ok" : 1,
   "operationTime" : Timestamp({t: 1510767613, i: 1}),
   "$gleStats" : {
      "lastOpTime" : Timestamp({t: 0, i: 0}),
      "electionId" : ObjectId("7fffffff0000000000000001")
   },
   "$clusterTime" : {
      "clusterTime" : Timestamp({t: 1510767613, i: 1}),
      "signature" : {
         "hash" : BinData(0,"IwBZ4SZjIMI5NdM62NObV/R31GM="),
         "keyId" : Long("6488693018630029321")
      }
   }
}

注意

mongos instances do not provide the shardingState.

警告

此命令在受影响的数据库上获得写锁（write lock），并在完成之前阻止其他操作；但是，该操作通常是短暂的。