v.19.14Improvement

Optimize Selecting of Smallest Column for SELECT Count() Query

Optimize selecting of smallest column for SELECT count() query. #6344 (Amos Bird)
Optimizes the selection of the smallest column to improve performance for SELECT count() queries in ClickHouse.

Why it matters

This feature improves query efficiency by choosing the smallest column when executing SELECT count() operations. It reduces resource usage and accelerates query execution, benefiting users with faster and more efficient counts on large datasets.

How to use it

This optimization is applied automatically in ClickHouse when running SELECT count() queries. No additional configuration or manual enablement is required from the user.