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
