Hi, Jark,
I'm very interested in this feature, and I'm also working on this
recently.
I just have a glance at the FLIP, it's good, but I found that there is
no plan to add SESSION windows.
Also, I think there can be more things we can do based on this new
syntax. For example,
- window sort support
- window union/intersect/minus support
- Improve dimension table join
We can have more deep discussion on this new feature later .
I've also opened an jira that is related to this feature recently:
https://issues.apache.org/jira/browse/FLINK-18830
Best!
PengchengLiu
在 2020/9/25 下午10:30，“Jark Wu”<imj...@gmail.com> 写入:
Hi everyone,
I want to start a FLIP about supporting windowing table-valued functions
(TVF).
The main purpose of this FLIP is to improve the near real-time (NRT)
experience of Flink.
FLIP-145:
https://cwiki.apache.org/confluence/display/FLINK/FLIP-145%3A+Support+SQL+windowing+table-valued+function
We want to introduce TUMBLE, HOP, CUMULATE windowing TVFs, the CUMULATE is
a new kind of window.
With the windowing TVFs, we can support richer operations on windows,
including window join, window TopN and so on.
This makes things simple: we only need to assign windows at the beginning
of the query, and then apply operations after that like traditional batch
SQL.
We hope it can help to reduce the learning curve of windows, improve NRT
for Flink, and attract more batch users.
A simple code snippet for 10 minutes tumbling window aggregate:
SELECT window_start, window_end, SUM(price)
FROM TABLE(
TUMBLE(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '10' MINUTES))
GROUP BY window_start, window_end;
I'm looking forward to your feedback.
Best,
Jark
