Re: flink1.9.1 RetractStream insert to mysql problem

Hi Polarisary, Look at the semantics your SQL wants to express: Top N, More practically is: Top 1. - Top N produce stream with primary keys contains row number, but your sql didn't select row number, so there is not primary key. - UpsertStreamTableSink requires primary key, So there is an exceptio

flink1.9.1 RetractStream insert to mysql problem

Hi, I use flink 1.9.1, sql as follows, INSERT INTO a SELECT c1, c2, c3, c4 FROM ( SELECT *,ROW_NUMBER() OVER (PARTITION BY c1, c2, c3 ORDER BY c4 DESC) AS rownum" + FROM t)