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Improve join cardinality estimation when there is no overlap in the min/max values #3802

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isidentical opened this issue Oct 11, 2022 · 0 comments · Fixed by #3848
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enhancement New feature or request

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@isidentical
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Is your feature request related to a problem or challenge? Please describe what you are trying to do.
If the min/max value of any join equijoin columns are not overlapping, and if the propagated statistics are exact, we can infer that the join will not produce any results back. Requires #3787

Describe the solution you'd like
Propagate the information about the correctness of the input statistics, so we can use it in the compute_inner_join_cardinality to decide whether to give up or say the selectivity is 0.

Describe alternatives you've considered
Not doing this. Currently we just give up and not provide any cost estimates.

Additional context
None, originally from #3787.

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