I was testing a local change to sqldiff.c [a] today and noticed that the subject invocation (with ... naming two, differing databases) produced an entirely empty "changeset" file. This is not what the [sqldiff doc](https://sqlite.org/sqldiff.html) indicates should happen. [a. The change is to optionally specify some non-PK column(s) that will not participate in the value comparison. It did not touch the changeset_one_table() function. ] Of course, wondering how I broke functionality I **tried** to not touch, I ran the "stock" version, one I downloaded as "sqlite-tools-win32-x86-3340100.zip", with the same arguments. It misbehaves the same way. Without the --changeset argument pair, both produce the expected SQL to alter one database to another. Is this a known non-feature of sqldiff? If so, the doc is wrong. Otherwise this lack of output must be a bug.