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Ingo Bürk edited comment on FLINK-22737 at 5/31/21, 7:14 AM: ------------------------------------------------------------- I discussed this again with Timo, and we will go with the Unix epoch instead of NULL now. To summarize: * CURRENT_WATERMARK(<column>) * Error if the provided column is not a rowtime column * The returned type is that of the provided column (TIMESTAMP / TIMESTAMP_LTZ), but we force the precision to 3. * If no watermark has been emitted yet, we return the Unix epoch. Edit: Sorry, I may have misunderstood my discussion with Timo. was (Author: airblader): I discussed this again with Timo, and we will go with the Unix epoch instead of NULL now. To summarize: * CURRENT_WATERMARK(<column>) * Error if the provided column is not a rowtime column * The returned type is that of the provided column (TIMESTAMP / TIMESTAMP_LTZ), but we force the precision to 3. * If no watermark has been emitted yet, we return the Unix epoch. > Add support for CURRENT_WATERMARK to SQL > ---------------------------------------- > > Key: FLINK-22737 > URL: https://issues.apache.org/jira/browse/FLINK-22737 > Project: Flink > Issue Type: Sub-task > Components: Table SQL / API > Reporter: David Anderson > Assignee: Ingo Bürk > Priority: Major > > With a built-in function returning the current watermark, one could operate > on late events without resorting to using the DataStream API. > Called with zero parameters, this function returns the current watermark for > the current row – if there is an event time attribute. Otherwise, it returns > NULL. -- This message was sent by Atlassian Jira (v8.3.4#803005)