Is there a way to extract the difference between table a in sqlite db file A and table b in sqlite db file B?

Question

I have two sqlite db file A and B. In them I have table a and b. Is there a way to extract the difference between A.a and B.b.

I found a similar question here. In that question, both tables are under the same db files.

Answer 1

Simply use ATTACH with whichever technique you choose.

See e.g. https://www.sqlite.org/lang_attach.html for details.