This is an automated email from the ASF dual-hosted git repository. qiaojialin pushed a commit to branch update_doc_for_flush in repository https://gitbox.apache.org/repos/asf/iotdb.git
commit 86a425f2b245159f31400cf59c949c799ac422b3 Author: qiaojialin <[email protected]> AuthorDate: Tue Nov 23 08:59:08 2021 +0800 add description for flush command --- docs/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md | 4 ++++ docs/zh/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md | 3 +++ 2 files changed, 7 insertions(+) diff --git a/docs/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md b/docs/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md index 12e9b3d..6dc104f 100644 --- a/docs/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md +++ b/docs/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md @@ -24,6 +24,10 @@ Persist all the data points in the memory table of the storage group to the disk, and seal the data file. +Note: This command does not need to be invoked manually by the client. IoTDB has WAL to ensure data security +and IoTDB will flush when appropriate. +Frequently call flush can result in small data files that degrade query performance. + ```sql IoTDB> FLUSH IoTDB> FLUSH root.ln diff --git a/docs/zh/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md b/docs/zh/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md index a20ec7e..e6c422a 100644 --- a/docs/zh/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md +++ b/docs/zh/UserGuide/IoTDB-SQL-Language/Maintenance-Command.md @@ -24,6 +24,9 @@ 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。 +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 root.ln
