Delete all keys from rocksdb (drop all)

Question

I have a rocksdb instance with multithreaded read/write access. At some point an arbitrary thread needs to process a request to clear the whole database, basically delete all keys. How can I do it with the smallest disturbance to the other threads? Obviously, as everything is parallel, there is no need for a definite moment at which the database gets cleared and the new writes go to an empty one, and it is okay if some parallel reads are still getting the old data for some time.

• I see DeleteRange, but my keys are irregular, there is no such thing as an upper bound
• I see DeleteFile, but the comment says it will be gone in rocksdb 7.0. Also, this looks like a bad idea in a multithreaded environmnet

Interestingly, I could not find a recipe for such seemingly common use case

Answer 1

I see DeleteRange, but my keys are irregular, there is no such thing as an upper bound

Do they have a common prefix? Generally you would prefix the keys with the 'table name' like 'users' or 'messages' and then you can drop the entire messages range which would be like dropping the entire table

If you don't - then I would suggest rereading the docs to make sure you are using rocksdb correctly but the only other option is to loop over and delete each entry

An alternative, is to grab a lock and swap out to a new clean DB and delete the old data folder entirely