give me an ex please
because this seems a lot like homework, i only offered a partial SQL to help you think about the issue;
this doesn't pass a syntax check but provides a couple of clues as to how to tackle the issue
SELECT * FROM (select row_number() over(partition by order by.....) As RW FROM SOMETABLE ) myAlias Where RW = 3
if you can show your work, and tell us what isn't working, we could help you understand the concepts behind solving the issue.
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