I got a diamond pickaxe and each ore out of creative mode (to see how much stuff they drop), then I went into survival mode to mine them, and they disappeared, dropping nothing

I went to mine the ores, but they dropped nothing
They just should've dropped something, but no, they didn't

I think this might've been a one-time bug, but here's how you make it happen (done in creative mode):

1. Get an ore (not sure if iron or gold works, didn't try. Nether quartz also works), and a diamond pickaxe
2. Go into survival mode, then place the ores.
3. Mine them with the diamond pickaxe
4. They do not drop anything