ClickHouse 25.12 introduces several performance optimizations and UX improvements. Numeric hints now display for all rows in multi-value results when space permits. The distinctJSONPaths function is 50x faster by using metadata instead of scanning JSON columns. DISTINCT queries on LowCardinality columns now operate on dictionary IDs rather than full values, improving performance up to 6x. SEMI JOIN queries benefit from filter pushdown optimization, reducing data scanned by 30% and improving query speed by similar margins.
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Numeric hint when last column and enough horizontal space #Optimize distinctJSONPaths aggregate function #Optimize DISTINCT transform for LowCardinality Columns #Use equivalent sets to push down filter for SEMI JOIN #Sort: