...大约 13 分钟
集群运维命令
展示集群配置
当前 IoTDB 支持使用如下 SQL 展示集群的关键参数：
SHOW VARIABLES
示例：
IoTDB> show variables
+----------------------------------+-----------------------------------------------------------------+
| Variables| Value|
+----------------------------------+-----------------------------------------------------------------+
| ClusterName| defaultCluster|
| DataReplicationFactor| 1|
| SchemaReplicationFactor| 1|
| DataRegionConsensusProtocolClass| org.apache.iotdb.consensus.iot.IoTConsensus|
|SchemaRegionConsensusProtocolClass| org.apache.iotdb.consensus.ratis.RatisConsensus|
| ConfigNodeConsensusProtocolClass| org.apache.iotdb.consensus.ratis.RatisConsensus|
| TimePartitionInterval| 604800000|
| DefaultTTL(ms)| 9223372036854775807|
| ReadConsistencyLevel| strong|
| SchemaRegionPerDataNode| 1.0|
| DataRegionPerDataNode| 5.0|
| LeastDataRegionGroupNum| 5|
| SeriesSlotNum| 10000|
| SeriesSlotExecutorClass|org.apache.iotdb.commons.partition.executor.hash.BKDRHashExecutor|
| DiskSpaceWarningThreshold| 0.05|
+----------------------------------+-----------------------------------------------------------------+
Total line number = 15
It costs 0.225s
注意： 必须保证该 SQL 展示的所有配置参数在同一集群各个节点完全一致
展示 ConfigNode 信息
当前 IoTDB 支持使用如下 SQL 展示 ConfigNode 的信息：
SHOW CONFIGNODES
示例：
IoTDB> show confignodes
+------+-------+---------------+------------+--------+
|NodeID| Status|InternalAddress|InternalPort| Role|
+------+-------+---------------+------------+--------+
| 0|Running| 127.0.0.1| 10710| Leader|
| 1|Running| 127.0.0.1| 10711|Follower|
| 2|Running| 127.0.0.1| 10712|Follower|
+------+-------+---------------+------------+--------+
Total line number = 3
It costs 0.030s
ConfigNode 状态定义
对 ConfigNode 各状态定义如下：
- Running: ConfigNode 正常运行
- Unknown: ConfigNode 未正常上报心跳
- 无法接收其它 ConfigNode 同步来的数据
- 不会被选为集群的 ConfigNode-leader
展示 DataNode 信息
当前 IoTDB 支持使用如下 SQL 展示 DataNode 的信息：
SHOW DATANODES
示例：
IoTDB> create timeseries root.sg.d1.s1 with datatype=BOOLEAN,encoding=PLAIN
Msg: The statement is executed successfully.
IoTDB> create timeseries root.sg.d2.s1 with datatype=BOOLEAN,encoding=PLAIN
Msg: The statement is executed successfully.
IoTDB> create timeseries root.ln.d1.s1 with datatype=BOOLEAN,encoding=PLAIN
Msg: The statement is executed successfully.
IoTDB> show datanodes
+------+-------+----------+-------+-------------+---------------+
|NodeID| Status|RpcAddress|RpcPort|DataRegionNum|SchemaRegionNum|
+------+-------+----------+-------+-------------+---------------+
| 1|Running| 127.0.0.1| 6667| 0| 1|
| 2|Running| 127.0.0.1| 6668| 0| 1|
+------+-------+----------+-------+-------------+---------------+
Total line number = 2
It costs 0.007s
IoTDB> insert into root.ln.d1(timestamp,s1) values(1,true)
Msg: The statement is executed successfully.
IoTDB> show datanodes
+------+-------+----------+-------+-------------+---------------+
|NodeID| Status|RpcAddress|RpcPort|DataRegionNum|SchemaRegionNum|
+------+-------+----------+-------+-------------+---------------+
| 1|Running| 127.0.0.1| 6667| 1| 1|
| 2|Running| 127.0.0.1| 6668| 0| 1|
+------+-------+----------+-------+-------------+---------------+
Total line number = 2
It costs 0.006s
DataNode 状态定义
DataNode 的状态机如下图所示：
对 DataNode 各状态定义如下：
- Running: DataNode 正常运行，可读可写
- Unknown: DataNode 未正常上报心跳，ConfigNode 认为该 DataNode 不可读写
- 少数 Unknown DataNode 不影响集群读写
- Removing: DataNode 正在移出集群，不可读写
- 少数 Removing DataNode 不影响集群读写
- ReadOnly: DataNode 磁盘剩余空间低于 disk_warning_threshold（默认 5%），DataNode 可读但不能写入，不能同步数据
- 少数 ReadOnly DataNode 不影响集群读写
- ReadOnly DataNode 可以查询元数据和数据
- ReadOnly DataNode 可以删除元数据和数据
- ReadOnly DataNode 可以创建元数据，不能写入数据
- 所有 DataNode 处于 ReadOnly 状态时，集群不能写入数据，仍可以创建 Database 和元数据
对于一个 DataNode，不同状态元数据查询、创建、删除的影响如下表所示：
| DataNode 状态 | 可读 | 可创建 | 可删除 |
|---|---|---|---|
| Running | 是 | 是 | 是 |
| Unknown | 否 | 否 | 否 |
| Removing | 否 | 否 | 否 |
| ReadOnly | 是 | 是 | 是 |
对于一个 DataNode，不同状态数据查询、写入、删除的影响如下表所示：
| DataNode 状态 | 可读 | 可写 | 可删除 |
|---|---|---|---|
| Running | 是 | 是 | 是 |
| Unknown | 否 | 否 | 否 |
| Removing | 否 | 否 | 否 |
| ReadOnly | 是 | 否 | 是 |
展示全部节点信息
当前 IoTDB 支持使用如下 SQL 展示全部节点的信息：
SHOW CLUSTER
示例：
IoTDB> show cluster
+------+----------+-------+---------------+------------+
|NodeID| NodeType| Status|InternalAddress|InternalPort|
+------+----------+-------+---------------+------------+
| 0|ConfigNode|Running| 127.0.0.1| 10710|
| 1|ConfigNode|Running| 127.0.0.1| 10711|
| 2|ConfigNode|Running| 127.0.0.1| 10712|
| 3| DataNode|Running| 127.0.0.1| 10730|
| 4| DataNode|Running| 127.0.0.1| 10731|
| 5| DataNode|Running| 127.0.0.1| 10732|
+------+----------+-------+---------------+------------+
Total line number = 6
It costs 0.011s
在节点被关停后，它的状态也会改变，如下所示：
IoTDB> show cluster
+------+----------+-------+---------------+------------+
|NodeID| NodeType| Status|InternalAddress|InternalPort|
+------+----------+-------+---------------+------------+
| 0|ConfigNode|Running| 127.0.0.1| 10710|
| 1|ConfigNode|Unknown| 127.0.0.1| 10711|
| 2|ConfigNode|Running| 127.0.0.1| 10712|
| 3| DataNode|Running| 127.0.0.1| 10730|
| 4| DataNode|Running| 127.0.0.1| 10731|
| 5| DataNode|Running| 127.0.0.1| 10732|
+------+----------+-------+---------------+------------+
Total line number = 6
It costs 0.012s
展示全部节点的详细配置信息：
SHOW CLUSTER DETAILS
示例：
IoTDB> show cluster details
+------+----------+-------+---------------+------------+-------------------+----------+-------+-------+-------------------+-----------------+
|NodeID| NodeType| Status|InternalAddress|InternalPort|ConfigConsensusPort|RpcAddress|RpcPort|MppPort|SchemaConsensusPort|DataConsensusPort|
+------+----------+-------+---------------+------------+-------------------+----------+-------+-------+-------------------+-----------------+
| 0|ConfigNode|Running| 127.0.0.1| 10710| 10720| | | | | |
| 1|ConfigNode|Running| 127.0.0.1| 10711| 10721| | | | | |
| 2|ConfigNode|Running| 127.0.0.1| 10712| 10722| | | | | |
| 3| DataNode|Running| 127.0.0.1| 10730| | 127.0.0.1| 6667| 10740| 10750| 10760|
| 4| DataNode|Running| 127.0.0.1| 10731| | 127.0.0.1| 6668| 10741| 10751| 10761|
| 5| DataNode|Running| 127.0.0.1| 10732| | 127.0.0.1| 6669| 10742| 10752| 10762|
+------+----------+-------+---------------+------------+-------------------+----------+-------+-------+-------------------+-----------------+
Total line number = 6
It costs 0.340s
展示 Region 信息
集群中以 SchemaRegion/DataRegion 作为元数据/数据的复制和管理单元，Region 的状态和分布对于系统运维和测试有很大帮助，如以下场景：
- 查看集群中各个 Region 被分配到了哪些 DataNode，是否均衡
- 查看集群中各个 Region 被分配了哪些分区，是否均衡
- 查看集群中各个 RegionGroup 的 leader 被分配到了哪些 DataNode，是否均衡
当前 IoTDB 支持使用如下 SQL 展示 Region 信息：
SHOW REGIONS: 展示所有 Region 分布SHOW SCHEMA REGIONS: 展示所有 SchemaRegion 分布SHOW DATA REGIONS: 展示所有 DataRegion 分布SHOW (DATA|SCHEMA)? REGIONS OF DATABASE <sg1,sg2,...>: 展示指定数据库 <sg1,sg2,...> 对应的 Region 分布SHOW (DATA|SCHEMA)? REGIONS ON NODEID <id1,id2,...>: 展示指定节点 <id1,id2,...> 对应的 Region 分布SHOW (DATA|SCHEMA)? REGIONS (OF DATABASE <sg1,sg2,...>)? (ON NODEID <id1,id2,...>)?: 展示指定数据库 <sg1,sg2,...> 在指定节点 <id1,id2,...> 对应的 Region 分布
展示所有 Region 的分布：
IoTDB> show regions
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 0| DataRegion|Running|root.sg1| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.013|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 3| 127.0.0.1| 6669| Leader|2023-03-07T17:32:18.398|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2| DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:20.011|
| 2| DataRegion|Running|root.sg2| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:20.395|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:19.450|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.637|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 12
It costs 0.165s
其中，SeriesSlotNum 指的是 region 内 seriesSlot 的个数。同样地，TimeSlotNum 也指 region 内 timeSlot 的个数。
展示 SchemaRegion 或 DataRegion 的分布：
IoTDB> show data regions
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 0| DataRegion|Running|root.sg1| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.013|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2| DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:20.011|
| 2| DataRegion|Running|root.sg2| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:20.395|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 6
It costs 0.011s
IoTDB> show schema regions
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 3| 127.0.0.1| 6669| Leader|2023-03-07T17:32:18.398|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:19.450|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.637|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 6
It costs 0.012s
展示指定数据库 <sg1,sg2,...> 对应的 Region 分布：
IoTDB> show regions of database root.sg1
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+-- -----+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 0| DataRegion|Running|root.sg1| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.013|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 3| 127.0.0.1| 6669| Leader|2023-03-07T17:32:18.398|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 6
It costs 0.007s
IoTDB> show regions of database root.sg1, root.sg2
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 0| DataRegion|Running|root.sg1| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.013|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 3| 127.0.0.1| 6669| Leader|2023-03-07T17:32:18.398|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2| DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:20.011|
| 2| DataRegion|Running|root.sg2| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:20.395|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:19.450|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.637|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 12
It costs 0.009s
IoTDB> show data regions of database root.sg1, root.sg2
+--------+----------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+----------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0|DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0|DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 0|DataRegion|Running|root.sg1| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.013|
| 2|DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2|DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:20.011|
| 2|DataRegion|Running|root.sg2| 1| 1| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:20.395|
+--------+----------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 6
It costs 0.007s
IoTDB> show schema regions of database root.sg1, root.sg2
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 3| 127.0.0.1| 6669| Leader|2023-03-07T17:32:18.398|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:19.450|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 3| 127.0.0.1| 6669|Follower|2023-03-07T17:32:19.637|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 6
It costs 0.009s
展示指定节点 <id1,id2,...> 对应的 Region 分布：
IoTDB> show regions on nodeid 1
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 4
It costs 0.165s
IoTDB> show regions on nodeid 1, 2
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:18.245|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2| DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:19.011|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:19.232|
| 3|SchemaRegion|Running|root.sg2| 1| 0| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:19.450|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 8
It costs 0.165s
展示指定数据库 <sg1,sg2,...> 在指定节点 <id1,id2,...> 对应的 Region 分布：
IoTDB> show regions of database root.sg1 on nodeid 1
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 1|SchemaRegion|Running|root.sg1| 1| 0| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.111|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 2
It costs 0.165s
IoTDB> show data regions of database root.sg1, root.sg2 on nodeid 1, 2
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
|RegionId| Type| Status|Database|SeriesSlotNum|TimeSlotNum|DataNodeId|RpcAddress|RpcPort| Role| CreateTime|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
| 0| DataRegion|Running|root.sg1| 1| 1| 1| 127.0.0.1| 6667|Follower|2023-03-07T17:32:18.520|
| 0| DataRegion|Running|root.sg1| 1| 1| 2| 127.0.0.1| 6668| Leader|2023-03-07T17:32:18.749|
| 2| DataRegion|Running|root.sg2| 1| 1| 1| 127.0.0.1| 6667| Leader|2023-03-07T17:32:19.834|
| 2| DataRegion|Running|root.sg2| 1| 1| 2| 127.0.0.1| 6668|Follower|2023-03-07T17:32:19.011|
+--------+------------+-------+--------+-------------+-----------+----------+----------+-------+--------+-----------------------+
Total line number = 4
It costs 0.165s
Region 状态定义
Region 继承所在 DataNode 的状态，对 Region 各状态定义如下：
- Running: Region 所在 DataNode 正常运行，Region 可读可写
- Unknown: Region 所在 DataNode 未正常上报心跳，ConfigNode 认为该 Region 不可读写
- Removing: Region 所在 DataNode 正在被移出集群，Region 不可读写
- ReadOnly: Region 所在 DataNode 的磁盘剩余空间低于 disk_warning_threshold（默认 5%），Region 可读，但不能写入，不能同步数据
单个 Region 的状态切换不会影响所属 RegionGroup 的运行，
在设置多副本集群时（即元数据副本数和数据副本数大于 1），
同 RegionGroup 其它 Running 状态的 Region 能保证该 RegionGroup 的高可用性。
对于一个 RegionGroup：
- 当且仅当严格多于一半的 Region 处于 Running 状态时， 该 RegionGroup 可进行数据的查询、写入和删除操作
- 如果处于 Running 状态的 Region 少于一半，该 RegionGroup 不可进行数据的数据的查询、写入和删除操作
展示集群槽信息
集群使用分区来管理元数据和数据，分区定义如下：
- 元数据分区：SeriesSlot
- 数据分区：<SeriesSlot，SeriesTimeSlot>
在文档Cluster-Concept中可以查看详细信息。
可以使用以下 SQL 来查询分区对应信息：
展示数据分区所在的 DataRegion
展示一个数据分区（或一个序列槽下的所有数据分区）所在的 DataRegion:
SHOW DATA REGIONID OF root.sg WHERE SERIESSLOTID=s0 (AND TIMESLOTID=t0)
有如下几点说明：
s0、t0均只能为数字。
TimeSlotId 是 SeriesTimeSlotId 的简称。
”SERIESSLOTID=s0”可以被替换为”DEVICEID=xxx.xx.xx“。 这样的话，sql会自动计算对应该设备id的序列槽。
同样的，"TIMESLOTID=t0"也可以被替换为"TIMESTAMP=t1"。这样，SQL会计算该时间戳对应的时间槽，也就是时间段包含该时间戳的时间槽。
示例:
IoTDB> show data regionid of root.sg where seriesslotid=5286 and timeslotid=0
+--------+
|RegionId|
+--------+
| 1|
+--------+
Total line number = 1
It costs 0.006s
IoTDB> show data regionid of root.sg where seriesslotid=5286
+--------+
|RegionId|
+--------+
| 1|
| 2|
+--------+
Total line number = 2
It costs 0.006s
展示元数据分区所在的 SchemaRegion
展示一个元数据分区所在的 SchemaRegion：
SHOW SCHEMA REGIONID OF root.sg WHERE SERIESSLOTID=s0
同样的，”SERIESSLOTID“与”TIMESLOTID“依然是可替换的。
示例:
IoTDB> show schema regionid of root.sg where seriesslotid=5286
+--------+
|RegionId|
+--------+
| 0|
+--------+
Total line number = 1
It costs 0.007s
展示序列槽下的时间槽
展示一个序列槽下的所有时间槽：
SHOW TIMESLOTID OF root.sg WHERE SERIESLOTID=s0 (AND STARTTIME=t1) (AND ENDTIME=t2)
示例:
IoTDB> show timeslotid of root.sg where seriesslotid=5286
+----------+
|TimeSlotId|
+----------+
| 0|
| 1000|
+----------+
Total line number = 1
It costs 0.007s
展示数据库的序列槽
展示一个数据库内，数据，元数据或是所有的序列槽：
SHOW (DATA|SCHEMA)? SERIESSLOTID OF root.sg
示例:
IoTDB> show data seriesslotid of root.sg
+------------+
|SeriesSlotId|
+------------+
| 5286|
+------------+
Total line number = 1
It costs 0.007s
IoTDB> show schema seriesslotid of root.sg
+------------+
|SeriesSlotId|
+------------+
| 5286|
+------------+
Total line number = 1
It costs 0.006s
IoTDB> show seriesslotid of root.sg
+------------+
|SeriesSlotId|
+------------+
| 5286|
+------------+
Total line number = 1
It costs 0.006s
迁移 Region
以下 SQL 语句可以被用于手动迁移一个 region， 可用于负载均衡或其他目的。
MIGRATE REGION <Region-id> FROM <original-DataNodeId> TO <dest-DataNodeId>
示例:
IoTDB> SHOW REGIONS
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
|RegionId| Type| Status| Database|SeriesSlotId|TimeSlotId|DataNodeId|RpcAddress|RpcPort| Role|
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 3| 127.0.0.1| 6670| Leader|
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 4| 127.0.0.1| 6681|Follower|
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 5| 127.0.0.1| 6668|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 1| 127.0.0.1| 6667|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 3| 127.0.0.1| 6670|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 7| 127.0.0.1| 6669| Leader|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 3| 127.0.0.1| 6670| Leader|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 4| 127.0.0.1| 6681|Follower|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 5| 127.0.0.1| 6668|Follower|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 1| 127.0.0.1| 6667|Follower|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 5| 127.0.0.1| 6668| Leader|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 7| 127.0.0.1| 6669|Follower|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 3| 127.0.0.1| 6670|Follower|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 4| 127.0.0.1| 6681| Leader|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 7| 127.0.0.1| 6669|Follower|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 1| 127.0.0.1| 6667| Leader|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 4| 127.0.0.1| 6681|Follower|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 5| 127.0.0.1| 6668|Follower|
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
Total line number = 18
It costs 0.161s
IoTDB> MIGRATE REGION 1 FROM 3 TO 4
Msg: The statement is executed successfully.
IoTDB> SHOW REGIONS
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
|RegionId| Type| Status| Database|SeriesSlotId|TimeSlotId|DataNodeId|RpcAddress|RpcPort| Role|
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 3| 127.0.0.1| 6670| Leader|
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 4| 127.0.0.1| 6681|Follower|
| 0|SchemaRegion|Running|root.test.g_0| 500| 0| 5| 127.0.0.1| 6668|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 1| 127.0.0.1| 6667|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 4| 127.0.0.1| 6681|Follower|
| 1| DataRegion|Running|root.test.g_0| 183| 200| 7| 127.0.0.1| 6669| Leader|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 3| 127.0.0.1| 6670| Leader|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 4| 127.0.0.1| 6681|Follower|
| 2| DataRegion|Running|root.test.g_0| 181| 200| 5| 127.0.0.1| 6668|Follower|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 1| 127.0.0.1| 6667|Follower|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 5| 127.0.0.1| 6668| Leader|
| 3| DataRegion|Running|root.test.g_0| 180| 200| 7| 127.0.0.1| 6669|Follower|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 3| 127.0.0.1| 6670|Follower|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 4| 127.0.0.1| 6681| Leader|
| 4| DataRegion|Running|root.test.g_0| 179| 200| 7| 127.0.0.1| 6669|Follower|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 1| 127.0.0.1| 6667| Leader|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 4| 127.0.0.1| 6681|Follower|
| 5| DataRegion|Running|root.test.g_0| 179| 200| 5| 127.0.0.1| 6668|Follower|
+--------+------------+-------+-------------+------------+----------+----------+----------+-------+--------+
Total line number = 18
It costs 0.165s