[Xapian-discuss] Seek help with simple writer/search using Perl

[James Aylett]

On Wed, Apr 11, 2007 at 11:23:12AM -0400, Jeff Anderson wrote:

> I understand the need to keep things flexible, but not providing a
> mechanism to store key/value data introduces its own kind of
> inflexibility by adding a dependency to some 3rd party storage
> device. I find that a very strange requirement of a storage device
> -- to require further storage devices to store your stuff. But to
> each his own i suppose. (But is that Edgar F. Codd i hear rolling in
> his grave?).

Say 90% of use will fit the Omega style storage. Then 90% of the
remaining would probably fit XML. 90% of the remaining might work as
JSON (which can cope with NUL, but loses the structure of XML). 90% of
the rest you might use ASN.1. The rest you'd probably key out into an
external storage system, so the only thing you want to store is an
identifier (which you could do simply in any of the previous).

You could use them *all* (except the last one) in a way that is
accessible as key-value pairs (with structure in the key name), but
may provide additional functionality on top of that (eg: XPath for
XML).

(In other words, you could have different physical storage behind the
same logical interface. Codd would be behind that all the way.)

That's one of the reasons we don't have this in the core, although the
discussions keep going slowly. I suspect we'll get something there in
the end, but I wouldn't like to venture what the storage format might be.

J

-- 
/--------------------------------------------------------------------------\
  James Aylett                                                  xapian.org
  james at tartarus.org                               uncertaintydivision.org