Are you seeking to persist your data between runs of your program? Or offload the data to disk becuase of volume and memory constraints?

If the former, it should be relatively trivial and safe. If the latter, with threads involved, it requires considerable thought and care. You might look at DBM::Deep, though there doesn't appear to be any mention of thread-safety one way or the other. It can certainly handle the hashes of hashes aspect, and has ACID transactions which might mean it would work from multiple threads.

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In reply to Re^3: Database in a folder? by BrowserUk
in thread Database in a folder? by AriSoft

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