feat: utilize the column cardinality for deciding whether to do dict #1372
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jiacai2050
reviewed
Dec 18, 2023
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During the time when you don't have write permission for a while, you can ping me if any prs are ready to merge. @apache/horaedb-committers |
jiacai2050
reviewed
Dec 20, 2023
tanruixiang
approved these changes
Dec 20, 2023
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Rationale
The column value set has been summarized into the meta data if the column is low distinct. With such information, the sampling for the columns can be skipped.
Detailed Changes
Skip sampling over the low-cardinality columns.
Test Plan
Updated the unit tests.