SQL & PL/SQL

Hello,

I'm trying to generate a unique random number with below query:

select trunc(dbms_random.value(1,12)) from dual connect by rownum <= 5;

but this query return duplicate values and if I add distinct then it returns less number of records means less than 5 records.

I want to generate a unique random number based on no. of rows like in above example 5 is max no of records, so it should generate 5 unique random values.

Please help me out.

Thanks in advance!!