RANDOM returns a FLOAT BINARY(53) random number generated using x as
the given seed. If x is omitted, the random number generated
is based on the seed provided by the last RANDOM invocation with a
seed, or on a default initial seed of 1 if RANDOM has not previously
been invoked with a seed.
>>-RANDOM--+-----+--------------------------------------------->< '-(x)-'
- x
- Expression. x must have a computational type and should
have an arithmetic type. If x is numeric, it must be real.
If x is not specified FIXED BINARY(31,0), it is converted.
Unless 0 < x < 2,147,483,646, the ERROR condition is raised.
The values generated by RANDOM are uniformly distributed between
0 and 1, with 0 < random(x) < 1. They are generated as follows
using the multiplicative congruential method:
seed(x) = mod(950706376 * seed(x - 1), 2147483647)
random(x) = seed(x) / 2147483647