[polli]

Originally Posted by theducks

Lots of deletions will leave invisible crumbs in the DB.
Run Library maintenance, it has a vacuuming stage as part of the check. Do checkout the FAQ at calibre-ebook.com (click Help in Calibre to get close to that)

Thanks but Where is the Library Maintenance?

I do look at the Calibre webpage but find it very hard to understand.