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From 徐涛 <happydexu...@gmail.com>
Subject Semantic when table joins table from window
Date Tue, 21 Aug 2018 10:19:49 GMT
Hi All,
	var praiseAggr = tableEnv.sqlQuery(s"SELECT article_id FROM praise GROUP BY HOP(updated_time,
INTERVAL '1' SECOND,INTERVAL '3' MINUTE) , article_id" )
	tableEnv.registerTable("praiseAggr", praiseAggr)
    var finalTable = tableEnv.sqlQuery(s”SELECT 1 FROM article a join praiseAggr p on a.article_id=p.article_id"
    tableEnv.registerTable("finalTable", finalTable)
	 I know that praiseAggr, if written to sink, is append mode , so if a table joins praiseAggr,
what the table “see”, is a table contains the latest value, or a table that grows larger
and larger? If it is the later, will it introduce performance problem?
	 Thanks a lot.

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