How can I get certain records from a table

[ocpdude]

how can I write a query to get records from n to m.
example

SELECT column_a
FROM table_name
WHERE rownum BETWEEN 10 and 20;
order by column_a

I am trying to get records between 10 and 20 only.

but the ROWNUM DOESN'T WORK IN THIS CASE.

hope this makes it more clear.


Thanks