Random number between two integers

• Siva Val
• Published: 18 Mar 2003

Though Oracle provides an internal function to generate random numbers, there is no function that gives a random number between any two given integers. Sometimes this is needed to pull random data for test cases. The following function generates a random number between any given two integers. The script is easily updatable to include pulling random_date between two given dates (by converting the date into a Julian date and converting back to date). It has been tested on v. 8.1.7.3.

create or replace function myrand(a IN int,b IN int) 
return number
is
begin
return trunc(abs(( GREATEST(a,b) - LEAST(a,b) + 1 ) * abs(dbms_random.value)) + LEAST(a,b));
end;
/

Here is an example:

1* select myrand(10,20) from dual
SQL> /

MYRAND(10,20)
-------------
18

SQL> select myrand(-1,-20) from dual
2 
SQL> /

MYRAND(-1,-20)
--------------
-16

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