How do you persist a BTree on disk?

[hosseinmoein]

Sorry if this question is already answered. But how do you persist/retrieve a BTree to/from disk? Can it be memory-mapped and brought in partially to memory?

Regards,
HM

[d-maurer]

Hossein Moein wrote at 2020-10-27 13:49 -0700:

Sorry if this question is already answered. But how do you persist/retrieve a BTree to/from disk? Can it be memory-mapped and brought in partially to memory?

Python's "pickle" module contains functionality to persist/retrieve a wide variety of Python objects to/from disk, among them `BTrees`.

[jamadden]

Except that pickling large BTrees does not actually work outside a system like ZODB. You get stack overflow errors if you try. I’m sure I opened an issue about that before. (Edit : #44)

[hosseinmoein]

ok, I was under the impression that BTree itself has persistence mechanism. I don't like pickle, but will look into it
thanks

[mgedmin]

BTrees is part of a persistence mechanism called ZODB. ZODB happens to be based on pickles.