Functions for Generating Pseudo-Random Numbers
Note
Non-cryptographic generators of pseudo-random numbers are used.
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.
Syntax
Arguments
- — resulting in any of the supported data types. The resulting value is discarded, but the expression itself if used for bypassing if the function is called multiple times in one query. Optional parameter.
Returned value
- Pseudo-random number.
Type: UInt32.
Example
Query:
Random Functions for Working with Strings
randomString
randomPrintableASCII
fuzzBits
Syntax
Inverts bits of s
, each with probability .
Arguments
- s
- or FixedString
- - constant Float32/64
Returned value
Fuzzed string with same as s type.
Example
``` text
┌─fuzzBits(materialize(‘abacaba’), 0.1)─┐
│ abaaaja │
│ a*cjab+ │
│ aeca2A │
└───────────────────────────────────────┘