well. It really depends. I'm not an expert on this, I'm just passing on my friends experience. I think what people might be looking for is experience, and being a barback helps.
But usually the bartending school will help you land a job. From what my friend told me, the schools have jobs lined up and ready to go with their graduates. So I'm pretty sure it won't be a problem. But if you're concerned, talk to the school and see if they guarantee you a job or what their placement percentage is. They should also have stats on what the average $/hour is too. So to find answers, just goto the school and they should be able to help you.
If they can't provide you with good stats, goto another school. Chances are if they dont' know, they are probably bad and don't want to tell you!!
Best of Luck!