I'm trying to do a project for a databases class where I have a user enter their current location and I tell them what constellations/planets/etc are visible in their area. I've seen this data compiled into images, PDFs, and website entries, but I can't seem to find a csv for it. I get that this data is bound to be massive or extremely complex, but I feel like there should be something out there. Any clues?
You can probably extract the data from Stellarium. Also, does it need to be all sky, or not? What Wavelength? If you want an all sky visible catalogue, the United States Navy produced the NOMAD catalog by combining 2MASS, UCAC, and the USNO-B catalog. You could also use the APASS all sky catalog, meant for helping astronomers with photometric calibration.
If you don't care about whether the wavelength is in the visible, CalTech's IRSA has a bunch of infrared source catalogs (the smallest/shallowest one being the IRAS catalog). The deepest all sky infrared catalogs are the WISE sets.
If you are looking for stars that are visible to the unaided eye, the Yale Bright Star Catalog is a good source. It includes 9100 stars to approximately magnitude 7 and is available in ASCII and binary formats -- perfect for your database project. Based on the date, time, latitude and longitude, you can calculate which stars are above the horizon.
As someone pointed out, the planets move day-to-day, week-to-week, or month-to-month through the constellations. (The Moon moves much faster than that, going through the complete zodiac in about 27.3 days.) You would need to calculate the position of the planets in order to determine if they are visible or not. That might be beyond the scope of your "database" project.