I have my band exam tomorrow and one of the things we have to play is D flat scale. I cannot remember it at all. If anyone can answer this as soon as possible that would be great.

If you know the C scale, then every note in the Db scale is one half-step higher. Hopefully I won't have to spell that out for you.

I realize your test has already happened by now, but I just gotta say something.
First of all, I'm sure you knew the test requirements before the day before the test. You had time to prepare.
Second, I just don't think I would have been doing you any favors spoon feeding you a scale for a test (yes, I saw your question with plenty of time to hand you the answer, I just chose not to). As a musician, it's important to learn what scales are, how they are formed, understand the half/step whole step patterns, the circle of fifths, key signatures. That way you won't need to ask anyone a scale ever again.
I guess it's a question of whether to give a man a fish and feed him for a day, or teach him to fish and feed him for a lifetime...
Consider a book by Ed Roseman called Music Theory for Practical People. It's a very well written, non instrument specific book on theory that won't put you right to sleep. It's very well laid out and very informative.
http://www.amazon.com/Edlys-Music-Theory-Practical-People/dp/0966161602/sr=8-1/qid=1169688616/ref=pd_bbs_sr_1/103-8995756-9266227?ie=UTF8&s=books

Hmmm. . . I think the postitions are 5,3,1,5,3,1,2,3. Play it and see if it sounds right. If not, switch the last to positions.

You beat me to it, Steve. I agree.

Also, NEVER think of scales in slide positions. Think of them in notes in a certain key.

couldn't you also memorize that the major scales are played in this order:

root,whole step, whole, half, whole, whole, half, octave

yes, half step/ whole step patterns are another great way to learn your scales (and learn to construct them yourself!)

yes, half step/ whole step patterns are another great way to learn your scales (and learn to construct them yourself!)

but it would be much more easy to just memorize the key, why would you want to do much more work than just doing something more simple. Heres something that I was taught to remember the scales.
For flats--GCF (Greatest Common Factor. Bead (like a bead you find on a bracelet. gcfbead.
Far Sharps, just reverse that order. daebfcg.
Knowing the steps will also help a lot.

easier? maybe, for the short run. But in reality, learning scales by half step/ whole step pattern may in fact be more beneficial. For major scales, you can memorize a bunch of key signatures, sure. OR you can memorize one half step/ whole step pattern.
Joe Jackson (band leader/arranger/lead trombonist with the USAF Airmen of Note wrote a fantastic article on his website about this very thing. The whole thing comes down to knowing your horn and your intervals well enough by rote that you can treat your horn the way you would a piano keyboard. It's very fascinating to read, and I recommend taking a look.
http://www.jazztbone.com/articles/chromatic_intervalic_approach.htm

1. The order of flats is very easy to memorize, but make sure you have them in the right order. B.E.A.D. (spelling bead) goes first, then G.C.F. And the sharps are that in reverse, F.C.G.D.A.E.B.

2. The reason I have my students learn scales first by knowing the key is that it translates better to reading anything in that key. If you learn, let's say, the Gb scale by root, whole, whole, half, whole, whole, whole, half, then you know that scale, but not necessarily the key. If you learn it by a scale with B.E.A.D.G. and C. flats, then you not only know the scale, but also the key. So, I would say learn the key AND and pattern, but the key would be more important to get good at. (The pattern is as important, but only for working on the scale and the inotnation and shape of that scale.)