Oracle : random sample of a percentage of rows
How to retrieve a random sample of a percentage of a table’s rows ? Here goes the shorty for Oracle. Maybe there is another solution. But that one worked for me.
select * from (select * from table order by dbms_random.value) where rownum <= (select count(*)*0.1 from table)
the dbms_random.value is the trick for the random sample and the count(*)*0.1 is for the ten percent.