Aman Sinha has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/17075 )

Change subject: IMPALA-10494: Making use of the min/max column stats to improve 
min/max filters
......................................................................


Patch Set 27:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/17075/19//COMMIT_MSG
Commit Message:

http://gerrit.cloudera.org:8080/#/c/17075/19//COMMIT_MSG@19
PS19, Line 19: show_column_minmax_stats
> I guess we have quite a bunch of .test files that are executed against all
Ok, yeah it makes sense that the same .test file is used for different 
formats..so will involve updating several of them (just for reference, I 
checked under testdata:
   testdata/workloads$ grep -r -i "show column stats" | cut -d ":" -f 1 | uniq 
| wc -l
15
It shows 15 files).

On extending the min/max to other formats, we could probably consider in the 
future .. any such stats should ideally be leveraged by either the optimizer 
(for selectivity estimate) or runtime rather than be only for informational 
purpose.

My other thought on this is that showing min/max stats should ideally be 
controlled through a syntax improvement.. e.g SHOW COLUMN STATS WITH MINMAX 
<table name>  rather than a query option.
But in the interest of moving this patch forward, I am ok with deferring such 
work.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I08581b44419bb8da5940cbf98502132acd1c86df
Gerrit-Change-Number: 17075
Gerrit-PatchSet: 27
Gerrit-Owner: Qifan Chen <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Qifan Chen <[email protected]>
Gerrit-Reviewer: Zoltan Borok-Nagy <[email protected]>
Gerrit-Comment-Date: Thu, 25 Mar 2021 17:37:26 +0000
Gerrit-HasComments: Yes

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