RAND

Returns a random floating-point value v in the range 0 <= v < 1.0. To obtain a random integer R in the range i <= R < j, use the expression FLOOR(i + RAND() * (j − i)).

If an integer argument N is specified, it is used as the seed value. For equal argument values, RAND(N) returns the same value each time , and thus produces a repeatable sequence of column values (last example).

Syntax

RAND(N)

Arguments

Arguments	Description
N	The numerical value.

Return Type

A Float64 data type value.

Examples

SELECT RAND();
+---------------------+
| rand()              |
+---------------------+
| 0.07669816779607708 |
+---------------------+

SELECT RAND(1), RAND(2);
+--------------------+--------------------+
| RAND(1)            | RAND(2)            |
+--------------------+--------------------+
| 0.9742447372584028 | 0.2973258311583632 |
+--------------------+--------------------+

SELECT number, RAND(1000 * number) from numbers(10);
+--------+-----------------------+
| number | RAND((1000 * number)) |
+--------+-----------------------+
|      0 |    0.7311134158637046 |
|      1 |   0.20926024019676037 |
|      2 |    0.3204522453024471 |
|      3 |   0.15414315241487253 |
|      4 |    0.3231494607676717 |
|      5 |  0.059500236508538085 |
|      6 |    0.7053594880492737 |
|      7 |    0.4848707366995819 |
|      8 |    0.2872295709183398 |
|      9 |    0.5819343845110294 |
+--------+-----------------------+

SELECT RAND(), RAND(0), RAND(10000), RAND(NULL) from numbers(10);
+---------------------+----------------------+---------------------+---------------------+
| RAND()              | RAND(0)              | RAND(10000)         | RAND(NULL)          |
+---------------------+----------------------+---------------------+---------------------+
|  0.8410192638206491 |   0.7311134158637046 |  0.9746737753675192 |   0.590583043081937 |
|  0.9356678073279926 |   0.7734601843532382 |  0.9819295977773548 | 0.19697177117599896 |
|  0.2746441697075338 | 0.025844634233355035 |  0.6053827707224846 |  0.6830698490445499 |
|  0.3092425785999753 |   0.5841592619362002 | 0.16167417938013184 |  0.7030024192421047 |
| 0.16685249404419444 |  0.26217063257252515 |  0.7859247691297169 |  0.2401736713222382 |
| 0.22077870630397123 |   0.7719869057468207 | 0.21038253398226503 |  0.9236027334502199 |
|  0.5202213774172745 |   0.2186969106715092 |  0.4705968522124563 |  0.9247213333056916 |
|  0.8547328275319827 |   0.7937134566691362 |  0.6019019906360323 | 0.33042828022969406 |
|  0.7626614422062121 |   0.7493384290992732 | 0.42479983417070444 | 0.48604290449390297 |
|  0.7180659634926269 |   0.9689377480023901 | 0.32660946286978787 |  0.7334682833042149 |
+---------------------+----------------------+---------------------+---------------------+

SELECT RAND(), RAND() from numbers(10);
+---------------------+---------------------+
| RAND()              | RAND()              |
+---------------------+---------------------+
| 0.36375269335997307 | 0.36375269335997307 |
| 0.09377635544457674 | 0.09377635544457674 |
|  0.8277016072035953 |  0.8277016072035953 |
|  0.4907032292521587 |  0.4907032292521587 |
|  0.8009654887127645 |  0.8009654887127645 |
|   0.158373699161646 |   0.158373699161646 |
|  0.9414531157798985 |  0.9414531157798985 |
|  0.6622571995881148 |  0.6622571995881148 |
| 0.25786072087383205 | 0.25786072087383205 |
|  0.3063851342553019 |  0.3063851342553019 |
+---------------------+---------------------+