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28 lines
1.0 KiB
Markdown
28 lines
1.0 KiB
Markdown
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---
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en_copy: true
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---
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# Functions for generating pseudo-random numbers {#functions-for-generating-pseudo-random-numbers}
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Non-cryptographic generators of pseudo-random numbers are used.
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All the functions accept zero arguments or one argument.
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If an argument is passed, it can be any type, and its value is not used for anything.
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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.
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## rand {#rand}
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Returns a pseudo-random UInt32 number, evenly distributed among all UInt32-type numbers.
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Uses a linear congruential generator.
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## rand64 {#rand64}
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Returns a pseudo-random UInt64 number, evenly distributed among all UInt64-type numbers.
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Uses a linear congruential generator.
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## randConstant {#randconstant}
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Returns a pseudo-random UInt32 number, The value is one for different blocks.
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[Original article](https://clickhouse.tech/docs/en/query_language/functions/random_functions/) <!--hide-->
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