random

description

Syntax

DOUBLE random() 返回0-1之间的随机数。

DOUBLE random(DOUBLE seed) 返回0-1之间的随机数，以seed作为种子。

BIGINT random(BIGINT a, BIGINT b) 返回a-b之间的随机数，a必须小于b。

别名：rand

example

  1. mysql> select random();
  2. +---------------------+
  3. | random()            |
  4. +---------------------+
  5. | 0.35446706030596947 |
  6. +---------------------+
  8. mysql> select rand(1.2);
  9. +---------------------+
  10. | rand(1)             |
  11. +---------------------+
  12. | 0.13387664401253274 |
  13. +---------------------+
  14. 1 row in set (0.13 sec)
  16. mysql> select rand(1.2);
  17. +---------------------+
  18. | rand(1)             |
  19. +---------------------+
  20. | 0.13387664401253274 |
  21. +---------------------+
  22. 1 row in set (0.11 sec)
  24. mysql> select rand(-20, -10);
  25. +------------------+
  26. | random(-20, -10) |
  27. +------------------+
  28. |              -13 |
  29. +------------------+
  30. 1 row in set (0.10 sec)

keywords

  1. RANDOM, RAND