Nope! The machines at TSA checkpoints aren't connected to a database of any sort. All of the info is encoded in the boarding pass in a PDF417 2D barcode.

If you can read PDF417 (Zebra Crossing, the barcode reader for Android, can do it somewhat unreliably if you make your own build and have a good phone camera - otherwise, there are online services that can extract PDF417 from an image) you can see the info for yourself.

And, more importantly, if you can read PDF417, you can make your own!

To connect those machines to a database would both involve a lot of infrastructure build-out (imagine the chaos if that system went down nationwide!) and a lot of information sharing and standardization between airlines and the government. Signing the barcodes is smart, and is how "mobile boarding passes" work, but because paper passes were standardized so long ago, there's no security in place.

I also suspect the current TSA checkpoint barcode readers aren't smart enough to actually check the signature in a mobile boarding pass, but I don't want to find out myself.