Shortest set? Well for a long time I DJed at a club that had the same band every Friday night. I opened and DJed the band’s two 45 min breaks. It was nice, as when the band played I could dance and mix with the crowd. The band members were real friendly and we got along well. However, the band leader did not like the fact that I could put more folks on the dance floor than the band and keep them there for the entire set. He was always trying to go long or cut me short. my sets would often end up being only 30 minutes. The longest? I’ve done several outdoor events where I had to DJ and MC the entire event, 9 to 10 hours, and in the hot Houston summer weather.