On Wed, 21 Dec 2005, Jim Gray wrote:
> Being a database guy... I assume they are everywhere. :)
>
> In general the cross match is not just spatial,
> it also has predicates on the "vital signs" like magnitude and
> morphology.
> And there are inner and outer joins and ...
sure, STIL does those too, I was simplifying a bit for brevity.
> So, my guess is that the data needs to have a schema and ...
> But.... I understand that if someone is building a portable client-side
> tool the "database" might be more like SleepyCat than MySQL or MsAccess.
What my algorithm sees is much less like a database than Berkeley DB/Sleepycat; for instance the tables to be matched may not exist in any persistent form, but only as data structures in memory (though for large tables it's likely to be on disk somewhere). But in the sense that it's working with a notional array of rows of values, with some columns which are marked as relevant to the crossmatching, you can call it a database if you like :-).
Mark
-- Mark Taylor Astronomical Programmer Physics, Bristol University, UK m.b.taylor@bris.ac.uk +44-117-928-8776 http://www.star.bris.ac.uk/~mbt/Received on 2005-12-21Z17:02:08