My backups have been bigger than I expected, so I wanted to answer the question “what files were added/changed in the last backup?” I started poking around my sqlite file, and I was able to answer the question, but I also ran into some surprises in the data I found. I’m wondering if this is expected, or if it’s indicative of some bug or corruption. I’m doing everything on a copy of the file, and duplicati had been idle for hours, with no journal on disk when I made the copy, so I would expect everything to be consistent, but it’s certainly possible sqlite doesn’t behave the way I expect somehow.
My most recent backup included only one Remotevolume of type Blocks, with ID = 4914. I discovered that there are blocks in this volume which do not appear to be associated with any blockset:
sqlite> select * from block where block.id = 15206372; 15206372|+Z2rItbOpGSVW1teA/SC/2PH2tyqWmylevJiIN5EEWE=|15680|4914 sqlite> select * from blocksetentry where blockid = 15206372; sqlite>
This is not the only such block; there are a lot of them:
sqlite> select count(*) from block where block.volumeid = 4914 and block.id not in (select blockid from blocksetentry); 56
In fact, there are similar orphaned block ids in nearly every volume I checked.
Is this normal? Is it possible my backup is missing the files which these blocks were part of?