Thanks for the survey! I'm also interested on the use cases of DataStream window join.
Best, Jark On Thu, 27 Aug 2020 at 14:40, Danny Chan <yuzhao....@gmail.com> wrote: > Hi, users, here i want to collect some use cases about the window join[1], > which is a supported feature on the data stream. The purpose is to make a > decision whether to support it also on the SQL side, for example, 2 > tumbling window join may look like this: > > ```sql > select ... window_start, window_end > from TABLE( > TUMBLE( > DATA => TABLE table_a, > TIMECOL => DESCRIPTOR(rowtime), > SIZE => INTERVAL '1' MINUTE)) tumble_a > [LEFT | RIGHT | FULL OUTER] JOIN TABLE( > TUMBLE( > DATA => TABLE table_b, > TIMECOL => DESCRIPTOR(rowtime), > SIZE => INTERVAL '1' MINUTE)) tumble_b > on tumble_a.col1 = tumble_b.col1 and ... > ``` > > I had some discussion off-line with some companies (Tencent, Bytedance and > Meituan), and it seems that interval join is the most common case. The > window join case is very few, so i'm looking forward there are some > feed-back here. > > Expecially, it is apprecaited if you can share the use cases of the window > join (using the Flink data stream or written by other programs) and why the > window-join is a must(can not replace with normal stream join or interval > join). > > Thanks in advance ~ > > [1] > https://ci.apache.org/projects/flink/flink-docs-release-1.11/dev/stream/operators/joining.html > > Best, > Danny Chan >
