SELECT * FROM BLAH WHERE fieldname in (1, 2, 3) equivilent in sf

[KidFix]

ello all

is there an equivilent to fieldname in (1, 2, 3) (i.e. shorthand version of fieldname=1 or fieldname=2 or fieldname=3) that can be used in an sf querystring I'm passing to a report? And is there any resource that tells me what can and can't be accepted in a passed sf? I've already tried putting fieldname in (1, 2, 3) in my sf with no success.

sorry for the somewhat garbled explanaition

Thanks in advance