v.20.3New Feature

Added system tables and functions for generating zeros in ClickHouse

Official CH changelog text
Added system tables system.zeros and system.zeros_mt as well as tale functions zeros() and zeros_mt(). Tables (and table functions) contain single column with name zero and type UInt8. This column contains zeros. It is needed for test purposes as the fastest method to generate many rows. This fixes #6604 #9593 (Nikolai Kochetov)
Introduced system.zeros and system.zeros_mt system tables along with zeros() and zeros_mt() table functions, each providing a single UInt8 column named zero filled with zero values.

Why it matters

These additions provide an extremely fast method to generate large numbers of rows containing zeroes, primarily for testing and benchmarking purposes, improving the efficiency and simplicity of generating dummy data in queries.

How to use it

Users can query the system tables directly using SELECT * FROM system.zeros or system.zeros_mt. Alternatively, users can invoke the table functions in the FROM clause using SELECT * FROM zeros() or SELECT * FROM zeros_mt() to generate the zero-filled rows on-demand.

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