mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-17 13:13:36 +00:00
19 lines
726 B
Markdown
19 lines
726 B
Markdown
# Functions for generating pseudo-random numbers
|
|
|
|
Non-cryptographic generators of pseudo-random numbers are used.
|
|
|
|
All the functions accept zero arguments or one argument.
|
|
If an argument is passed, it can be any type, and its value is not used for anything.
|
|
The only purpose of this argument is to prevent common subexpression elimination, so that two different instances of the same function return different columns with different random numbers.
|
|
|
|
## rand
|
|
|
|
Returns a pseudo-random UInt32 number, evenly distributed among all UInt32-type numbers.
|
|
Uses a linear congruential generator.
|
|
|
|
## rand64
|
|
|
|
Returns a pseudo-random UInt64 number, evenly distributed among all UInt64-type numbers.
|
|
Uses a linear congruential generator.
|
|
|