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| # 运维命令 |
| |
| ## FLUSH |
| |
| 将指定存储组的内存缓存区 Memory Table 的数据持久化到磁盘上，并将数据文件封口。在集群模式下，我们提供了持久化本节点的指定存储组的缓存、持久化整个集群指定存储组的缓存命令。 |
| |
| 注意：此命令客户端不需要手动调用，IoTDB 有 wal 保证数据安全，IoTDB 会选择合适的时机进行 flush。 |
| 如果频繁调用 flush 会导致数据文件很小，降低查询性能。 |
| |
| ```sql |
| IoTDB> FLUSH |
| IoTDB> FLUSH ON LOCAL |
| IoTDB> FLUSH ON CLUSTER |
| IoTDB> FLUSH root.ln |
| IoTDB> FLUSH root.sg1,root.sg2 ON LOCAL |
| IoTDB> FLUSH root.sg1,root.sg2 ON CLUSTER |
| ``` |
| |
| ## MERGE |
| |
| 触发层级合并和乱序合并。当前 IoTDB 支持使用如下两种 SQL 手动触发数据文件的合并： |
| |
| * `MERGE` 先触发层级合并，等层级合并执行完后，再触发乱序合并。在乱序合并中，仅重写重复的 Chunk，整理速度快，但是最终磁盘会存在多余数据。 |
| * `FULL MERGE` 先触发层级合并，等层级合并执行完后，再触发乱序合并。在乱序合并中，将需要合并的顺序和乱序文件的所有数据都重新写一份，整理速度慢，最终磁盘将不存在无用的数据。 |
| |
| ```sql |
| IoTDB> MERGE |
| IoTDB> FULL MERGE |
| ``` |
| 同时，在集群模式中支持对本节点或整个集群手动触发数据文件的合并: |
| ```sql |
| IoTDB> MERGE ON LOCAL |
| IoTDB> MERGE ON CLUSTER |
| IoTDB> FULL MERGE ON LOCAL |
| IoTDB> FULL MERGE ON CLUSTER |
| ``` |
| |
| ## CLEAR CACHE |
| |
| |
| 手动清除chunk, chunk metadata和timeseries metadata的缓存，在内存资源紧张时，可以通过此命令，释放查询时缓存所占的内存空间。在集群模式下，我们提供了清空本节点缓存、清空整个集群缓存命令。 |
| |
| ```sql |
| IoTDB> CLEAR CACHE |
| IoTDB> CLEAR CACHE ON LOCAL |
| IoTDB> CLEAR CACHE ON CLUSTER |
| ``` |
| |
| |
| ## SET SYSTEM TO READONLY / RUNNING |
| |
| 手动设置系统为正常运行、只读状态。在集群模式下，我们提供了设置本节点状态、设置整个集群状态的命令，默认对整个集群生效。 |
| |
| ```sql |
| IoTDB> SET SYSTEM TO RUNNING |
| IoTDB> SET SYSTEM TO READONLY ON LOCAL |
| IoTDB> SET SYSTEM TO READONLY ON CLUSTER |
| ``` |
| |
| ## 终止查询 |
| |
| IoTDB 支持设置 Session 连接超时和查询超时时间，并支持手动终止正在执行的查询。 |
| |
| ### Session 超时 |
| |
| Session 超时控制何时关闭空闲 Session。空闲 Session 指在一段时间内没有发起任何操作的 Session。 |
| |
| Session 超时默认未开启。可以在配置文件中通过 `session_timeout_threshold` 参数进行配置。 |
| |
| ### 查询超时 |
| |
| 对于执行时间过长的查询，IoTDB 将强行中断该查询，并抛出超时异常，如下所示： |
| |
| ```sql |
| IoTDB> select * from root.**; |
| Msg: 701 Current query is time out, please check your statement or modify timeout parameter. |
| ``` |
| |
| 系统默认的超时时间为 60000 ms，可以在配置文件中通过 `query_timeout_threshold` 参数进行自定义配置。 |
| |
| 如果您使用 JDBC 或 Session，还支持对单个查询设置超时时间（单位为 ms）： |
| |
| ```java |
| ((IoTDBStatement) statement).executeQuery(String sql, long timeoutInMS) |
| session.executeQueryStatement(String sql, long timeout) |
| ``` |
| |
| > 如果不配置超时时间参数或将超时时间设置为负数，将使用服务器端默认的超时时间。 |
| > 如果超时时间设置为0，则会禁用超时功能。 |
| |
| ### 查询终止 |
| |
| 除了被动地等待查询超时外，IoTDB 还支持主动地终止查询，命令为： |
| |
| ```sql |
| KILL QUERY <queryId> |
| ``` |
| |
| 通过指定 `queryId` 可以中止指定的查询，而如果不指定 `queryId`，将中止所有正在执行的查询。 |
| |
| 为了获取正在执行的查询 id，用户可以使用 `show query processlist` 命令，该命令将显示所有正在执行的查询列表，结果形式如下： |
| |
| | Time | queryId | statement | |
| |------|---------|-----------| |
| | | | | |
| |
| 其中 statement 最大显示长度为 64 字符。对于超过 64 字符的查询语句，将截取部分进行显示。 |
| |
| ## 集群节点分布式监控工具 |
| |
| ### 查看 DataNode 信息 |
| |
| 当前 IoTDB 支持使用如下 SQL 查看 DataNode 的信息： |
| |
| ``` |
| SHOW DATANODES |
| ``` |
| |
| 示例： |
| |
| ```sql |
| 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 regions |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| |RegionId| Type|Status|storage group|Series Slots|Time Slots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| | 0|SchemaRegion| Up| root.sg| 2| 0| 1|127.0.0.1| 6667|Leader| |
| | 1|SchemaRegion| Up| root.ln| 1| 0| 2|127.0.0.1| 6668|Leader| |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| Total line number = 2 |
| It costs 0.013s |
| |
| IoTDB> show datanodes |
| +------+-------+---------+-------+-------------+---------------+ |
| |NodeID| Status| Host|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 regions |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| |RegionId| Type|Status|storage group|Series Slots|Time Slots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| | 0|SchemaRegion| Up| root.sg| 2| 0| 1|127.0.0.1| 6667|Leader| |
| | 1|SchemaRegion| Up| root.ln| 1| 0| 2|127.0.0.1| 6668|Leader| |
| | 2| DataRegion| Up| root.ln| 1| 1| 1|127.0.0.1| 6667|Leader| |
| +--------+------------+------+-------------+------------+----------+----------+---------+-------+------+ |
| Total line number = 3 |
| It costs 0.008s |
| IoTDB> show datanodes |
| +------+-------+---------+-------+-------------+---------------+ |
| |NodeID| Status| Host|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 |
| 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 将认为该 DataNode 不可读写 |
| - **Removing**: DataNode 正在移出集群，不可读写 |
| - **ReadOnly**: DataNode 磁盘剩余空间低于 disk_full_threshold（默认 5%），此 DataNode 将不再能写入，不再能同步数据 |
| |
| ### 查看 ConfigNode 节点信息 |
| |
| 当前 IoTDB 支持使用如下 SQL 查看 ConfigNode 的信息： |
| |
| ``` |
| SHOW CONFIGNODES |
| ``` |
| |
| 示例： |
| |
| ``` |
| IoTDB> show confignodes |
| +------+-------+-------+------------+--------+ |
| |NodeID| Status| Host|InternalPort| Role| |
| +------+-------+-------+------------+--------+ |
| | 0|Running|0.0.0.0| 22277| Leader| |
| | 1|Running|0.0.0.0| 22279|Follower| |
| | 2|Running|0.0.0.0| 22281|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 |
| |
| ### 查看全部节点信息 |
| |
| 当前 IoTDB 支持使用如下 SQL 查看全部节点的信息： |
| |
| ``` |
| SHOW CLUSTER |
| ``` |
| |
| 示例： |
| |
| ``` |
| IoTDB> show cluster |
| +------+----------+-------+---------+------------+ |
| |NodeID| NodeType| Status| Host|InternalPort| |
| +------+----------+-------+---------+------------+ |
| | 0|ConfigNode|Running| 0.0.0.0| 22277| |
| | 1|ConfigNode|Running| 0.0.0.0| 22279| |
| | 2|ConfigNode|Running| 0.0.0.0| 22281| |
| | 3| DataNode|Running|127.0.0.1| 9003| |
| | 4| DataNode|Running|127.0.0.1| 9005| |
| | 5| DataNode|Running|127.0.0.1| 9007| |
| +------+----------+-------+---------+------------+ |
| Total line number = 6 |
| It costs 0.011s |
| ``` |
| |
| ## 集群 Region 分布监控工具 |
| |
| 集群中以 Region 作为数据复制和数据管理的单元，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 |
| |
| 当前 IoTDB 支持使用如下 SQL 查看 Region： |
| |
| - `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 STORAGE GROUP <sg1,sg2,...>`: 展示指定存储组 <sg1,sg2,...> 对应的 Region 分布 |
| |
| 展示所有 Region 的分布： |
| ``` |
| IoTDB> show regions |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 0| DataRegion|Running| root.sg1| 1| 1| 1|0.0.0.0| 6667|Follower| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 2|0.0.0.0| 6668| Leader| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 2|0.0.0.0| 6668|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 3|0.0.0.0| 6669| Leader| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 1|0.0.0.0| 6667| Leader| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 2|0.0.0.0| 6668|Follower| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 2|0.0.0.0| 6668| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 3|0.0.0.0| 6669|Follower| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 12 |
| It costs 0.165s |
| ``` |
| |
| 展示 SchemaRegion 或 DataRegion 的分布： |
| ``` |
| IoTDB> show data regions |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 0| DataRegion|Running| root.sg1| 1| 1| 1|0.0.0.0| 6667|Follower| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 2|0.0.0.0| 6668| Leader| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 1|0.0.0.0| 6667| Leader| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 2|0.0.0.0| 6668|Follower| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 3|0.0.0.0| 6669|Follower| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 6 |
| It costs 0.011s |
| |
| IoTDB> show schema regions |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 2|0.0.0.0| 6668|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 3|0.0.0.0| 6669| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 2|0.0.0.0| 6668| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 3|0.0.0.0| 6669|Follower| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 6 |
| It costs 0.012s |
| ``` |
| |
| 展示指定存储组 <sg1,sg2,...> 对应的 Region 分布： |
| ``` |
| IoTDB> show regions of storage group root.sg1 |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 0| DataRegion|Running| root.sg1| 1| 1| 1|0.0.0.0| 6667|Follower| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 2|0.0.0.0| 6668| Leader| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 2|0.0.0.0| 6668|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 3|0.0.0.0| 6669| Leader| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 6 |
| It costs 0.007s |
| |
| IoTDB> show regions of storage group root.sg1, root.sg2 |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 0| DataRegion|Running| root.sg1| 1| 1| 1|0.0.0.0| 6667|Follower| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 2|0.0.0.0| 6668| Leader| |
| | 0| DataRegion|Running| root.sg1| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 2|0.0.0.0| 6668|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 3|0.0.0.0| 6669| Leader| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 1|0.0.0.0| 6667| Leader| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 2|0.0.0.0| 6668|Follower| |
| | 2| DataRegion|Running| root.sg2| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 2|0.0.0.0| 6668| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 3|0.0.0.0| 6669|Follower| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 12 |
| It costs 0.009s |
| |
| IoTDB> show data regions of storage group root.sg1, root.sg2 |
| +--------+----------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+----------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 0|DataRegion|Running| root.sg1| 1| 1| 1|0.0.0.0| 6667|Follower| |
| | 0|DataRegion|Running| root.sg1| 1| 1| 2|0.0.0.0| 6668| Leader| |
| | 0|DataRegion|Running| root.sg1| 1| 1| 3|0.0.0.0| 6669|Follower| |
| | 2|DataRegion|Running| root.sg2| 1| 1| 1|0.0.0.0| 6667| Leader| |
| | 2|DataRegion|Running| root.sg2| 1| 1| 2|0.0.0.0| 6668|Follower| |
| | 2|DataRegion|Running| root.sg2| 1| 1| 3|0.0.0.0| 6669|Follower| |
| +--------+----------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 6 |
| It costs 0.007s |
| |
| IoTDB> show schema regions of storage group root.sg1, root.sg2 |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| |RegionId| Type| Status|Storage Group|SeriesSlots|TimeSlots|DataNodeId| Host|RpcPort| Role| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 2|0.0.0.0| 6668|Follower| |
| | 1|SchemaRegion|Running| root.sg1| 1| 0| 3|0.0.0.0| 6669| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 1|0.0.0.0| 6667|Follower| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 2|0.0.0.0| 6668| Leader| |
| | 3|SchemaRegion|Running| root.sg2| 1| 0| 3|0.0.0.0| 6669|Follower| |
| +--------+------------+-------+-------------+-----------+---------+----------+-------+-------+--------+ |
| Total line number = 6 |
| It costs 0.009s |
| ``` |
| |
| ### Region 状态定义 |
| 对 Region 各状态定义如下： |
| |
| - **Running**: Region 正常运行，可读可写 |
| - **Removing**: Region 所在 DataNode 正在被移出集群，不可读写 |
| - **Unknown**: Region 所在 DataNode 未正常上报心跳，ConfigNode 认为该 Region 不可读写 |
| |
| ## 集群槽路径监控工具 |
| |
| 集群使用分片来管理数据和元数据，一个存储组的元数据分片定义为序列槽，而数据分片定义为<序列槽，时间分区槽>的数对。为了得到分片相关的信息，可以使用以下SQL来查询： |
| ### 追踪数据分片的分区 |
| |
| 追踪一个数据分片（或一个序列槽下的所有数据分片）的对应分区: |
| - `SHOW DATA REGIONID OF root.sg WHERE SERIESSLOTID=s0 (AND TIMESLOTID=t0)` |
| |
| 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 |
| ``` |
| |
| ### 追踪元数据分片的分区 |
| 追踪一个元数据分片下的对应分区： |
| - `SHOW SCHEMA REGIONID OF root.sg WHERE SERIESSLOTID=s0` |
| |
| 示例: |
| ``` |
| IoTDB> show schema regionid of root.sg where seriesslotid=5286 |
| +--------+ |
| |RegionId| |
| +--------+ |
| | 0| |
| +--------+ |
| Total line number = 1 |
| It costs 0.007s |
| ``` |
| ### 追踪序列槽下的时间槽 |
| 展示一个存储组内，一个特定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 |
| ``` |
| ### 追踪存储组的序列槽 |
| 展示一个存储组内，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 |
| ``` |
| #### 注意: |
| 通常情况下，一个存储组内，数据和元数据的序列槽是相同的。然而，我们仍然提供了不同的sql语句，以防它们在某些情况下并不相同。 |
