Details
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Improvement
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Resolution: Fixed
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Major - P3
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None
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None
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None
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Fully Compatible
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QO 2022-11-14
Description
Investigate what is the best cardinality estimate of the minimum value of a given data type, e.g. empty string. When the value falls inside of a bucket we can estimate the equality as follows:
1) use the equality frequency for the inner bucket values (rangeFreq / NDV)
2) use kMinCard = 0.01 (if the value actually exists in the data, this will lead to underestimation).