Online Meeting (Tencent Meeting or VooV Meeting):
Time: 2021-01-17 9:00 PM Beijing Time
Host：Steve Yurong Su
Agenda
Status Updates
[VOTE] Apache IoTDB 0.11.2 RC4 release
Bugfix list:
* IOTDB-1049 Fix Nullpointer exception and a delete bug in Last query
* IOTDB-1060 Support full deletion for delete statement without where clause
* IOTDB-1068 Fix Time series metadata cache bug
* IOTDB-1069 restrict the flushing memtable number to avoid OOM when
mem_control is disabled
* IOTDB-1077 add insertOneDeviceRecords API in java session
* IOTDB-1087 fix compaction block flush: flush do not return until
compaction finished
* IOTDB-1106 Delete timeseries statement will incorrectly delete other
timeseries
* Github issue-2137 fix grafana value-time position bug
* Github issue-2169 GetObject returns String for all data types
* Github issue-2240 fix Sync failed: Socket is closed by peer
* Github issue-2387 The deleteData method exists in Session but not in
SessionPool.
* add thrift_max_frame_size in iotdb-engine.properties
* Fix incorrect last result after deleting all data
* Fix compaction recover block restart: IoTDB cannot restart until last
compaction recover task finished
* Fix compaction ignore modification file: delete does not work after
compaction
* print more insert error message in client
* expose enablePartition parameter into iotdb-engines.properpties
New Features
#2389 Add limit & offset clauses for show devices
在SHOW DEVICES语句中支持limit和offset
PR: https://github.com/apache/iotdb/pull/2389
SHOW DEVICES LIMIT 2 OFFSET 1
问题：没有修改用户文档
ISSUE: User documentation has not been modified
#2352 Add timeout mechanism for query processing
支持对查询设置超时
PR: https://github.com/apache/iotdb/pull/2352
SHOW QUERY PROCESSLIST
KILL QUERY INT?
问题：
没有维护thrfit/rpc-changelist.md 文件
Python/Cpp/Go Client中没有对应的接口
ISSUE:
The thrfit/rpc-changelist.md file is not maintained
There is no corresponding interface in Python/Cpp/Go Client
#2397 Add insertOneDeviceRecords API in java session
在Session中增加insertOneDeviceRecords接口，插入同属于一个device的多个 Record
PR: https://github.com/apache/iotdb/pull/2397
void insertRecordsOfOneDevice(
String deviceId,
List<Long> times,
List<List<String>> measurementsList,
List<List<TSDataType>> typesList,
List<List<Object>> valuesList)
ISSUE:
There is no corresponding interface in Python/Cpp/Go Client
#2340 Create interface of TimeIndex
增加创建TimeIndex的接口
PR: https://github.com/apache/iotdb/pull/2340/
Create interface of TimeIndex as ITimeIndex, and supply two default implement methods: DeviceTimeIndex and FileTimeIndex.
Design document: https://cwiki.apache.org/confluence/display/IOTDB/Interface+design+of+TsFileResource
#2417 Built-in UDTFs
增加内置UDTF
PR: https://github.com/apache/iotdb/pull/2417
User Doc: https://iotdb.apache.org/UserGuide/Master/Operation%20Manual/DML%20Data%20Manipulation%20Language.html#time-series-generating-functions
Demos:
Welcome to contribute UDFs, it's super easy!
https://iotdb.apache.org/UserGuide/Master/Operation%20Manual/UDF%20User%20Defined%20Function.html#contribute-udf
TBD
1. compares to influx in terms of performance
https://iotdb.apache.org/UserGuide/Master/Comparison/TSDB-Comparison.html
upgrade version 0.8.0→0.11.1 - xiangdong
tsbs benchmark: timescaledb、influxdb
2. Website
chinese ppt
ApacheCon - use cases
https://iotdb.apache.org/Community/Materials.html upgrade 2020 - xiangdong
3. best contributor monthly- need discuss and proposal (zhouyurun)
PR / review / mailing list / WeChat official account / doc / event(activity) / stackoverflow, csdn
Open Floor
new ideas, feedback, suggestions.
[Discussion] Enable Github Projects?
Doris
https://github.com/apache/incubator-doris/projects?query=is%3Aopen+sort%3Aupdated-desc
Druid
[Discussion] Github Bots
https://github.com/marketplace
Dependabot, Codecov, Imgbot, PEP 8 Speaks, Labelbot
Hi,
Thanks for letting us know so many good tools.
I do not believe code changes by robots very much unless I read the code
changes myself.
But I also think having such tools can help us saving time.
- Mergify: I do not like it. :( I think it is dangerous...
- Dependabot: I like this tool. (But we'd better to have a full test, as
some dependencies may lead to performance reduction when it fixes
something.
- Codecov: Well, if someone can set this up, I opt for it! I have spent
more than 3 days to fix the coveralls... but failed. We need code coverage
checking very much.
- Imgbot: OK from my view, as we have few images in the repo.
- Pull Request Size: OK from my view.
- PEP 8 Speaks: I like it.
Best,
-----------------------------------
Xiangdong Huang
School of Software, Tsinghua University
Coveralls Bots
Coveralls 的配置：建议通过环境变量传入 TOKEN，避免直接在 Github Actions 的 YAML 中使用明文的 TOKEN
Coveralls configuration: It is recommended to pass in TOKEN through environment variables to avoid using plaintext TOKEN directly in YAML of Github Actions.
https://github.com/apache/commons-pool/pull/60
Bots for C++/Go/Py Client?
Python client: refer to Apache Superset / enable PEP8
CALL FOR MAINTAINERS!
https://github.com/apache/iotdb/issues/2490
Clear:
http://doris.incubator.apache.org/master/en/extending-doris/udf/user-defined-function.html
Not very clear:
https://iotdb.apache.org/UserGuide/Master/Operation%20Manual/UDF%20User%20Defined%20Function.html
CALL FOR MAINTAINERS!
[Discussion] LAST_VALUE & LAST
https://github.com/apache/iotdb/issues/2395
Q:
I see there are two operators in IoTDB: last_value and last
I only see some differences in the output format. Are there any other differences?
A:
last is an individual statement, while last_value is an aggregation function. That means, you can use last_value attached with group by statement.
if you have no filters (where clause, or just where time > ?), then use last, it is far faster than last_value.Otherwise, you have to use last_value.
select last_value(s1), last_value(s2) from root.sg.d;
select last(s1), last(s2) from root.sg.d;
select last s1, s2 from root.sg.d
Discussion: Should last be a function name or a keyword?
Need further discussion.
[Discussion] New Feature: Nested Query
CALL FOR CONTRIBUTORS!
7th Meeting Schedule
Host: Zesong