[Sugar-devel] Technique to extract all records from xapian DB?

[Tomeu Vizoso]

On Wed, Dec 16, 2009 at 17:48, Martin Langhoff
<martin.langhoff at gmail.com> wrote:
> On Fri, Dec 11, 2009 at 2:35 PM, Tomeu Vizoso <tomeu at sugarlabs.org> wrote:
>> I think it's worth trying, but not sure if worth merging and
>> deploying. 0.82 didn't used directly the python xapian bindings, but
>> some wrapper on top of it that tried to make easier the mapping
>> between keys in the B-tree and metadata values.
>
> Yeah. It's a very complex beast that, after following the callstack
> hither and yon, only makes a v simple mapping. I've written a 20 line
> mini-reader class using xapian directly. Instead of following the DS
> code, I used the CLI tools that xapian includes, and it is a trivial
> thing. Needs a bit more time but it'll work.

Sounds good, if you need later to move to python, we can do something
easily if we know the prefixes for each field.

>> The mapping mentioned before is persisted in index/config inside the DS dir.
>
> Ah, it's not static? The number-field mapping It seems stable to me
> testing it. So the right way is to read that 'config', how do you
> parse it?

I think it should be stable for the fields we care about, which is a fixed set:

http://git.sugarlabs.org/projects/sugar-datastore/repos/mainline/blobs/sucrose-0.82/src/olpc/datastore/model.py#line379

Regards,

Tomeu

> Good that I asked.
>
>
>
> m
> --
>  martin.langhoff at gmail.com
>  martin at laptop.org -- School Server Architect
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