Solve direct read issue with low cardinality text columns#87994
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Ergus merged 14 commits intoClickHouse:masterfrom Oct 21, 2025
Merged
Solve direct read issue with low cardinality text columns#87994Ergus merged 14 commits intoClickHouse:masterfrom
Ergus merged 14 commits intoClickHouse:masterfrom
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When the input column is low cardinality, it seems like hasToken and similar functions are reported also as low cardinality result type in the dag. This is strictly true, but for direct read the column will contain only 0 and 1. So it is simpler and easier just set it as UInt8 explicitly in all the cases. Maybe one day we will have some boolean support in columns (storing internally some bitmap) and we can use that specialization.
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rschu1ze
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ahmadov
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Oct 2, 2025
rschu1ze
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Oct 5, 2025
Update test 02346_text_index_bug87887.sql
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ahmadov
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When the input column for is low cardinality, it seems like hasToken and similar functions are reported also as low cardinality result type in the dag.
This is strictly true, but for direct read the column will contain only 0 and 1. So it is simpler and easier just set it as UInt8 explicitly in all the cases.
Maybe one day we will have some boolean support in columns (storing internally some bitmap) and we can use that specialization.
Resolves: #87887
Resolves: #88119
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