Fucun Chu has posted comments on this change. ( http://gerrit.cloudera.org:8080/17744 )
Change subject: IMPALA-10835: Extend the DS_HLL_SKETCH function to accept a precision ...................................................................... Patch Set 2: (2 comments) http://gerrit.cloudera.org:8080/#/c/17744/1/be/src/exprs/aggregate-functions-ir.cc File be/src/exprs/aggregate-functions-ir.cc: http://gerrit.cloudera.org:8080/#/c/17744/1/be/src/exprs/aggregate-functions-ir.cc@1722 PS1, Line 1722: nctionCon > precision is not the best name. I would suggest following the datasketches Done http://gerrit.cloudera.org:8080/#/c/17744/1/be/src/exprs/aggregate-functions-ir.cc@1826 PS1, Line 1826: _cast<datask > why max here, not the specified precision? The resulting accuracy of a sketch returned at the end of the unioning process will be a function of the smallest of <i>lg_max_k</i> and <i>lg_config_k</i> that the union operator has seen. see: https://github.com/apache/datasketches-cpp/blob/master/hll/include/hll.hpp#L404-L407 In order not to affect the union operation of the high-precision ds_hll_sketch result sketch, lg_max_k takes the maximum value. If necessary, precision parameters will be added to ds_hll_union in the new jira -- To view, visit http://gerrit.cloudera.org:8080/17744 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I91a360bb046d4abb101641772b6159308bf6c014 Gerrit-Change-Number: 17744 Gerrit-PatchSet: 2 Gerrit-Owner: Fucun Chu <[email protected]> Gerrit-Reviewer: Alexander Saydakov <[email protected]> Gerrit-Reviewer: Csaba Ringhofer <[email protected]> Gerrit-Reviewer: Fucun Chu <[email protected]> Gerrit-Reviewer: Gabor Kaszab <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Comment-Date: Sun, 26 Sep 2021 10:42:09 +0000 Gerrit-HasComments: Yes
