Hi everyone, I am having some problems in the process of using flink sql, my sql is as follows:
SELECT COUNT(DISTINCT mm.student_id),sum(price) FROM ( SELECT a.student_id,a.confirm_date_time,sum(a.real_total_price)as price FROM ( SELECT DISTINCT po.id as order_id ,po.student_id ,po.create_id ,po.paid_date_time ,po.confirm_date_time ,po.real_total_price from `pack_order` po left join user1 u on u.id=po.student_id WHERE po.status='PAY_CONFIRMED' AND po.real_total_price>500 AND po.confirm_date_time >= '2018-09-27' and po.confirm_date_time < '2018-09-28' AND po.type IN (1,2) AND u.id is null )a join pack_order1 por on a.student_id=por.student_id GROUP BY a.student_id,a.confirm_date_time HAVING MIN(por.confirm_date_time)=a.confirm_date_time )mm I registered 3 tables by receiving data from 3 kafka topics (each topic represents a table, each topic has only one partition), and then calculated by flink sql, the result is sent again to a kafka topic, The same partition I used, my final calculation is a count value and a sum value. According to my understanding, the final result of kafka should always be incremented, but the final result is as follows: <http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/file/t1671/%E5%9B%BE%E7%89%87.png> The result marked in the figure is our final result, and the last result is not, that is, the final calculation result is wrong. By observing the final result, we find that the data will increase first, then decrease, and then increase. This situation is unexplained. We need the value of count and sum to be incremented in kafka. Because our goal is to achieve real-time display, Can you please explain why this happens and how to avoid it? thank you very much best wishes! -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/