[ownedbycats]

I accidentally erased timestamps of a few books while working in Calibre. No big deal:

1. Close Calibre.
2. Grab latest db backup open in SQLiteStudio.
3. Go to books table, find book, copy timestamp column.
4. Go to my library db. Paste the timestamp into same book.
5. Commit.

I've done this before with custom column, never directly on books column. It didn't work this time. SQLIteStudio reported on commit:
[11:19:09] An error occurred while committing the data: no such function: title_sort

What does this mean?

I can restore the date through GUI, will lose exact timestamp info though.