I tried to use write a nested query with HOP window in a streaming environment. Table `source` consists of 3 column, a, b, and timestamp. SELECT a FROM (SELECT a, COUNT(*) FROM source GROUP BY HOP(timestamp, ..., ...), a, b) GROUP BY HOP(timestamp, ..., ...), a HAVING ... And flink throws an exception of "Column 'timestamp' not found in any table". And I tried to "SELECT HOP_END(timestamp, ..., ...) AS timestamp, a, COUNT(*)" in the inner query, getting an exception of "Window can only be defined over a time attribute column." Can I make the rowtime attribute propagating to the outer query, just like chaining windows in DataStream API? Regrads, Bill |
Hi Bill,
you can use HOP_ROWTIME()/HOP_PROCTIME() to propagate the time attribute to the outer query. See also [1] for an example. Regards, Timo [1] https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/table/sql.html#selecting-group-window-start-and-end-timestamps Am 3/5/18 um 11:26 AM schrieb 杨力:
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Thanks. It works. I missed it while reading the document.
Timo Walther <[hidden email]> 于 2018年3月5日周一 下午9:20写道:
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