[Dxspider-support] SQL Support

[Dirk Koopman]

On Thu, 2006-01-12 at 00:47 +0100, Rub=?ISO-8859-1?B?6Q==?=n Navarro
Huedo wrote:
> Hello friends:
> I have been some moths out of this list.
> I have been reading in Changes about SQL feature.
> Where could i read more about it?

Unfortunately: nowhere, nor for the XML protocol based either.

When I have a (much more) complete implementation of either SQL or XML,
be assured that I shall announce it here first. 

However, to explain a bit what I am doing:-

For SQL: I have, for some considerable time, been unhappy about DB_File
and the Berkeley database. The reason for this is that it is extremely
fragile. Despite my best efforts it is still possible to corrupt
(mainly) the user file and dupefile. Usually this has to do with an
unclean exit, but (I believe) not always. Also, I am interested in the
possibilities that a SQL database may give me in, for instance: speed
and multiple processes reading and writing to it. Interestingly: I have
experimented with sticking the Spot database into various makes of SQL
database (something easy to do in perl) and come to the surprising
conclusion that it may not be worthwhile either in terms of speed, or
flexibility compared to the flat file system that is there. But I
suspect I shall be moving over to SQLite as a replacement for DB_File
which is not used for Spots. 

For XML: I am playing with a more or less drop in functional replacement
for the current PC protocol in XML. It also has the necessary bits added
(missing in PC protocol) to allow plug and play internode connections
(no more loops). This (for those that know about it) builds and improves
on the things I learned doing the Aranea version of the software (which
is now consigned to a branch in CVS). At least to start with, the two
protocols will coexist on inter-DXSpider links that enable it. In fact
nodes are free to use either or both at the same time. Eventually I
envisage all connections that use XML to speak just XML and that
includes all connections to "user front end" programs. 

Dirk G1TLH
-- 
Dirk Koopman <djk at tobit.co.uk>