v.19.17Improvement

Better Null Format for Tcp Handler, So That It's Possible to Use Select Ignore() from Table Format Null for Perf Measure via Clickhouse-client #7606 (amos Bird)

Official CH changelog text
Better Null format for tcp handler, so that it's possible to use select ignore(<expression>) from table format Null for perf measure via clickhouse-client #7606 (Amos Bird)
Improved Null output format for TCP handler allowing SELECT IGNORE(<expression>) FROM table FORMAT Null for performance measurement via clickhouse-client.

Why it matters

This feature enables users to perform performance measurements more efficiently by using the Null format over TCP, ignoring the actual output data. It helps in reducing overhead when running queries purely for benchmarking or testing, improving user experience during performance diagnostics.

How to use it

Users can utilize this feature by executing queries with the syntax:

SELECT IGNORE(<expression>) FROM <table> FORMAT Null

via the clickhouse-client over TCP to measure query performance without processing output data.

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