Manuzhai wrote at 2007-9-18 12:46 +0200:
> ...
>the Documentation link points to a page
>that seems to mostly have papers and presentation from 2000-2002.

There is a good guide to the ZODB from Andrew Kuchling (or similar).

It may be old -- but everything is still valid.

>On the internet, there is some talk about the different storage
>providers, but it seems mostly very old. FileStorage seems to be the
>only "serious" Storage provider delivered with ZODB. Are there any
>other general-purpose Storage providers actively being used in the

"FileStorage" is must faster than all other storages. Therefore,
it dominates the scene.

"DirectoryStorage", too, is used more widely.

Internally, "TemporaryStorage" is used (a RAM based storage for
sessions). DemoStorage is used for unit tests.

>How does their performance compare? FileStorage apparently needs
>to keep some index in memory; when does this start to be a problem?

You need about 30 bytes per object. You can calculate when
this starts to make problems for your.

>What's new in ZODB4?

I know nothing about ZODB4. The current version is near 3.8, maybe.

>There is some talk about blobs, are they
>described somewhere?

There should be a proposal at "";.
But, I just checked, there is not :-(

But a search for "ZODB Blob" gives quite a few hits.

For more information about ZODB, see the ZODB Wiki:

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