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Ruben Q L commented on CALCITE-4208: ------------------------------------ Thanks for your feedback [~amaliujia]. To be honest I am not quite sure about INNER/LEFT/RIGHT modifications. I am sure though that the ANTI computation must be fixed. > Improve metadata row count for Join > ----------------------------------- > > Key: CALCITE-4208 > URL: https://issues.apache.org/jira/browse/CALCITE-4208 > Project: Calcite > Issue Type: Improvement > Components: core > Reporter: Ruben Q L > Priority: Major > > Currently, the default metadata row count for join > {{RelMdRowCount#getRowCount(Join rel, RelMetadataQuery mq)}} relies on > {{RelMdUtil.getJoinRowCount}}. This method has several issues: > - In case of ANTI join, it returns the same estimation as a SEMI join > - In other cases (INNER, LEFT, RIGHT, FULL), it returns always the same > formula: > {{leftRowCount * rightRowCount * mq.getSelectivity(join, condition)}} > which seems valid for an INNER join, but not for LEFT / RIGHT / FULL. -- This message was sent by Atlassian Jira (v8.3.4#803005)