Sure, you can write a SQL query with multiple interval joins that preserve event-time attributes and watermarks. There's no need to feed data back to Kafka just to inject it again to assign new watermarks.
Am Di., 5. Mai 2020 um 01:45 Uhr schrieb lec ssmi <shicheng31...@gmail.com>: > I mean using pure sql statement to make it . Can it be possible? > > Fabian Hueske <fhue...@gmail.com> 于2020年5月4日周一 下午4:04写道： > >> Hi, >> >> If the interval join emits the time attributes of both its inputs, you >> can use either of them as a time attribute in a following operator because >> the join ensures that the watermark will be aligned with both of them. >> >> Best, Fabian >> >> Am Mo., 4. Mai 2020 um 00:48 Uhr schrieb lec ssmi < >> shicheng31...@gmail.com>: >> >>> Thanks for your replay. >>> But as I known, if the time attribute will be retained and the time >>> attribute field of both streams is selected in the result after joining, >>> who is the final time attribute variable? >>> >>> Benchao Li <libenc...@gmail.com> 于2020年4月30日周四 下午8:25写道： >>> >>>> Hi lec, >>>> >>>> AFAIK, time attribute will be preserved after time interval join. >>>> Could you share your DDL and SQL queries with us? >>>> >>>> lec ssmi <shicheng31...@gmail.com> 于2020年4月30日周四 下午5:48写道： >>>> >>>>> Hi: >>>>> I need to join multiple stream tables using time interval join. >>>>> The problem is that the time attribute will disappear after the jon , and >>>>> pure sql cannot declare the time attribute field again . So, to make is >>>>> success, I need to insert the last result of join to kafka ,and consume >>>>> it and join it with another stream table in another flink job . This >>>>> seems >>>>> troublesome. >>>>> Any good idea? >>>>> >>>>> >>>>> >>>> >>>> -- >>>> >>>> Benchao Li >>>> School of Electronics Engineering and Computer Science, Peking University >>>> Tel:+86-15650713730 >>>> Email: libenc...@gmail.com; libenc...@pku.edu.cn >>>> >>>>
