[Enhancement] improve the performance of multi distinct  #9400

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• I had searched in the issues and found no similar issues.

Description

Single point aggregation is a problem when multi DISTINCT is used in select statements。for example：

SELECT COUNT(DISTINCT k1) , COUNT(DISTINCT k2) FROM tbl WHERE dt >= 20211001 AND dt <= 20220406 

This statement may take tens of seconds

Solution

I want it to go faster

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

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