Alternative to ROWNUM needed in the SQL statement attached

Question

Hi,
I need an alternative to the use of
ROWNUM in the below SQL so that it
can work even if I use it in Sybase sql anywhere DB.
As I can't use rownum in sybase sql anywhere,
I need to know if I can get a result similar
to what the below query fetches using any
other means in Oracle.
SELECT field1, field2
FROM table1
WHERE rownum <= 20
Hope some one can help me.
Regards,
Magge

Answer 1

Can you use ROWID instead of ROWNUM? If so:
SELECT a.field1, a.field2
FROM table1 a
WHERE 20 >=
(SELECT COUNT (*) + 1
FROM table1 b
WHERE b.ROWID < a.ROWID)
Or, if you can't use ROWID, then:
SELECT a.field1, a.field2
FROM table1 a
WHERE 20 >=
(SELECT COUNT (*) + 1
FROM table1 b
WHERE b.field1 &#0124; &#0124; ' '&#0124; &#0124; b.field2 < a.field1 &#0124; &#0124; ' ' &#0124; &#0124; a.field2)
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