On Sep 10, 2007, at 10:34 AM, Alan Runyan wrote:
Hi guys.
It seems that one of our customers has a corrupted BTree. I would love
for someone to provide some insight on how we can recover the data.
we have two databases: 1 for resources and 1 for 'content'. resources
contain lots of very big files.
The system is configured to have a mount point at /plone/resources is
a subclass of BTreeFolder, using internal data struct of OOBTree.
And, as you said in another node, the BTree folder actually loves in
the resources database.
anytime I iterate over the keys I get POSKeyError. anytime I iterate
over the values the same. if I run BTree.check() on the data
structure's tree attribute (the OOBTree itself) I get a POSKeyError.
Running the utils.checkbtrees doesnt say this btree has a problem.
While debugging this I had a conversation with sidnei about mounted
databases. He recalled that if your using a mounted database you
should not pack. If for some reason your mounted database had a cross
reference to another database and somehow you had a dangling reference
to the other database it would cause POSKeyError.
Cross database references are inherently weak. A reference from a
foreign database doesn't prevent an object from being treated as
garbage. So, if the only reference to an object is from a foreign
database, then the object is considered garbage. It doesn't sound
like this is what's affecting you. The cross-database reference is
to the BTree. It sounds like the internal references are within
database.
Is there any other ways of "testing consistency" of FileStorage
other than:
- checkbtrees.py
- fstest.py
There's an fsrefs script that checks internal references I believe.
And any ideas how I can salvage the data? This BTree, of course, had
the most valuable data.
Possibly, there's a backup that has data records for the missing OIDs.
Jim
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Jim Fulton mailto:[EMAIL PROTECTED] Python
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