Jean-Michel POURE kirjutas N, 22.05.2003 kell 11:38:
> Dear all,
>
> A friend of mine needs to import and query a very large amount of data, coming
> from real-time acquisition systems.
What kind of querying does he need ?
You could check out Telegraph for continuous queries
http://telegraph.cs.berkeley.edu/
> The database is growing fast, several
> Tetra-bytes a day.
if you mean terabytes TB then 1 TB/day ~= 12.7 MB/sec, just about as
fast as you can write on an average ide drive if you do nothing else, or
what can come in over a 100 base T ethernet.
even in ide disks (the biggest available disks apiece) you have to add 5
disks a day just to store the incoming 1TB/day.
> What is the advancement of the community in the field of very large databases?
> Could you point out to me some useful information, techdocs, etc...?
no ;)
> Are there working groups, private fundings in this precise field?
dunno..
You are possibly on the verge of impossible ?
If you can hardly write down the data due to physical constraints
(memory and bus speeds) , it is very hard to also query it, unless you
deploy some terribly clever techniques which extract and compress your
data before it even gets to your DB ;)
Perhaps you (or your friend) are after filtering and not queries at all
?
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Hannu