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From hequn8128 <...@git.apache.org>
Subject [GitHub] flink issue #5347: [FLINK-8492][table] Fix calc cost bug
Date Thu, 25 Jan 2018 11:59:48 GMT
Github user hequn8128 commented on the issue:

    hi @fhueske @twalthr , the pr has been updated. It would be great if you can take a look
at it.
    Changes mainly include: 
    1. Adapt estimateRowCount to be more accurate. The original implementation use a constant
0.75 to reduce the result which makes row count of merged calc bigger than the row count of
un-merged calcs. Current implementation use a more accurate selectivity to reduce the result
row count.
    2. Merge calcs in convert rule of correrate. Double check to make sure unsupported exception
won't be thrown


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