Answer Posted / sunil bisht

Hi Prakash,

You did one mistake in this query when you are use rownum
is always start fetch the record from very first record
from table
Row num can work only with the follow using operators

=(only with 1)(select * from emp where rownum=1;) if you
are use 2 or other number in place of 1 so result is no
data found;

<(any vlaue)(select * from emp where rownum<12 if you are
using the > sign in place of < sign so result is no data
found

<=(any value)

Between 1 and any value

>=(only with 1)

<>(any value) this will return all records less than the
given value


if you want to retrive last three records from table then
you can used

select * from emp where rownum<=(select count(*) from emp)
minus select *from emp where rownum <=(select count(*)-3
from emp)

you get the last three record from the table

other method is

select * from emp e where 3>(select count(*) from emp d
where d.rowid>e.rowid);

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