[elephant-devel] Database trouble

[Leslie P. Polzer]

> I've been using elephant 0.91 for quite a while now, with a berkeley 4.6
> backend, and it's been a joy.

Great! :)


> Recently however, as usage has gone up, some problems have started occuring.
> One big problem has been that when I run (get-instances-by-class 'foo) I get
> a list of foo, but with some nil's occuring as well.
> Is this a sign of database corruption?

Not necessarily, I'd rather guess at a bug in the indexing mechanism
that has been solved by now.


> How do I remedy this?

Some possible solutions:

  * upgrade your Elephant

  * rebuild your indices

  * wrap your get-instances stuff in a function that removes
    the NIL entries


> I've tried running both the recover and checkpoint tools on the db, but
> no change.

No, that won't help. :)


> I've experienced deadlocks as well, and had to kill my sbcl

FYI you can prevent deadlocks from appearing.


> - wondering if that (non clean shutdown) is what caused the problems
> in the first place.

I don't think so.


> Or is this something to do with indexes - could they be remade somehow?

I think there was an easy way but I can't remember it right now...

  Cheers,

    Leslie

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