Quick tip: If you are using SQL Prompt and suggestions don’t seem to be working in a new database (but ARE working in other databases), it may be that you have it set up to only show suggestions for certain databases:

This was driving me absolutely crazy for almost a week. I couldn’t figure out why suggestions weren’t working, and all my Google searches were not revealing anything useful. I happened upon this earlier today, and life is right with the universe again.
Hopefully this helps someone else. (Yes, I probably changed this setting some time ago, but it has been so long I forgot about it!)