feat(planner): Introduce histogram in column statistics #9310
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BohuTANG
approved these changes
Dec 21, 2022
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Summary
This PR introduces the histogram to represent data distribution of column.
With histogram, we can compute selectivity of filters and cardinality of relational operators.
In this PR, we only support generating histograms in uniform distribution with NDV and row count. And only limited data types are supported. More functions will be implemented later.