flink 去重

LOCALTIMESTAMP as time_stamp

ts as case when time is null then CURRENT_TIMESTAMP else TO_TIMESTAMP_LTZ(time, 0) end ,

watermark for ts as ts - interval '60' second

PARTITION BY 的都有回撤流

group by 的没有回撤流 因为算的是指标

开窗又慢

SELECT *
FROM (
    SELECT 
       *
        ROW_NUMBER() OVER (PARTITION BY id ORDER BY time_stamp) AS rn
    FROM events
    WHERE time_stamp >= NOW() - INTERVAL '7' DAY
) t
WHERE rn = 1;