stats: correct fast analyze stats caclulation #10766
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Codecov Report
@@ Coverage Diff @@
## master #10766 +/- ##
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- Coverage 80.9332% 80.9093% -0.024%
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Files 419 419
Lines 88746 88750 +4
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- Hits 71825 71807 -18
- Misses 11690 11711 +21
- Partials 5231 5232 +1 |
winoros
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/run-all-tests |
eurekaka
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Jun 20, 2019
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/run-sqllogic-test-2 |
alivxxx
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What problem does this PR solve?
The stats built from fast analyze were wrong:
TotColSizewas the column size in the sample, not thetotalcolumn size.rowCount/sampleSize, even if the value just occurred once, which will overestimate the row count, and it also conflicts with the calculation ofdefaultValue, which treat the only once items the same as the values that do not occur.What is changed and how it works?
rowCount/sampleSize.defaultValueas their row count.Check List
Tests
Unit test
Code changes
Has exported function/method change
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