Allow broker to automatically rewrite expensive function to its approximate counterpart

[Jackie-Jiang]

• Allow broker to automatically rewrite expensive function to its approximate counterpart
  • DISTINCT_COUNT -> DISTINCT_COUNT_SMART_HLL
  • PERCENTILE -> PERCENTILE_SMART_TDIGEST
• Add table level override for the rewrite through the query config

Release-Notes

Add broker config pinot.broker.use.approximate.function to turn the feature on (off by default)
Add query config useApproximateFunction to override the broker level config

[codecov-commenter]

Codecov Report

Merging #8655 (c036b99) into master (ec42a3a) will increase coverage by 0.05%.
The diff coverage is 78.18%.

@@             Coverage Diff              @@
##             master    #8655      +/-   ##
============================================
+ Coverage     70.35%   70.40%   +0.05%     
  Complexity     4406     4406              
============================================
  Files          1690     1690              
  Lines         88187    88249      +62     
  Branches      13190    13204      +14     
============================================
+ Hits          62042    62135      +93     
+ Misses        21856    21829      -27     
+ Partials       4289     4285       -4     

Flag	Coverage Δ
integration1	27.47% <24.54%> (+0.02%)	⬆️
integration2	25.57% <24.54%> (-0.10%)	⬇️
unittests1	66.16% <100.00%> (-0.02%)	⬇️
unittests2	14.35% <55.45%> (+0.04%)	⬆️

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Impacted Files	Coverage Δ
...va/org/apache/pinot/spi/utils/CommonConstants.java	21.31% <ø> (ø)
...roker/requesthandler/BaseBrokerRequestHandler.java	70.37% <77.77%> (+1.02%)	⬆️
...org/apache/pinot/spi/config/table/QueryConfig.java	90.90% <100.00%> (+37.57%)	⬆️
...nt/local/startree/v2/store/StarTreeDataSource.java	40.00% <0.00%> (-13.34%)	⬇️
...mmon/request/context/predicate/NotEqPredicate.java	61.53% <0.00%> (-7.70%)	⬇️
...transform/function/IsNotNullTransformFunction.java	67.85% <0.00%> (-7.15%)	⬇️
...ot/segment/local/startree/OffHeapStarTreeNode.java	65.90% <0.00%> (-6.82%)	⬇️
...core/startree/operator/StarTreeFilterOperator.java	88.02% <0.00%> (-4.23%)	⬇️
...ava/org/apache/pinot/core/plan/FilterPlanNode.java	80.45% <0.00%> (-1.51%)	⬇️
...perator/filter/SortedIndexBasedFilterOperator.java	85.71% <0.00%> (-0.96%)	⬇️
... and 18 more

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