Semantic when table joins table from window

[徐涛]

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.


Best, 
Henry