I added a switch to a light that used to operate with a pull chain. Before I plaster my wall I wanted to add a wall sconce to be operated by the same wall switch so I can have both lights on at the same time. Can I simply run the black wire from the light to the switch and the white wire to the switch or must I make a different connection?

White goes to white, no whites to the switch, black from power and black from light goes to switch.

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I stand corrected, in this situation(a switch loop)does use the white and the black, the white should be identified at both ends with black tape to show it is now a Hot.
I don't do switch loops, Too many times a receptacle is necessary at switch location, with a switch loop, you have no neutral.
They are commonly done and is safe and acceptable for code. I know I could get future work If I did a switch loop, and now they want a receptacle?