- From: Emanuele D'Arrigo <manu3d@gmail.com>
- Date: Wed, 26 Sep 2007 12:33:22 +0100
- To: "Semantic Web Interest Group" <semantic-web@w3.org>, "public-owl-dev@w3.org" <public-owl-dev@w3.org>
On 9/26/07, Renato Golin <renato@ebi.ac.uk> wrote: > I'm quite interested in triplet storages but what I found is that there > is no consensus nor standard for anything in that area. In hindsight, I believe my question was a bit hopeless: as Arjohn says it's unlikely that a consensus will ever develop on the matter. There will be various options with pros and cons. My bad. =) I guess my question really had to be more in the direction of: are there two or three architectures for triplets storage to choose from? > There are several storage engines but each one doing it's own way. > Also, the support to query languages is quite random. Indeed I seem to have noticed that. Is the field still so novel that there are no full implementation of RQL? Yet, the specifications seems to have been stable for some time... =? > Given the amount of data you can have the hash table might not fit in > any computer and even if it fits, I/O will become a huge problem. > This is a common misconception that hash tables are always faster than > lists but that's not true, especially when you have bigger hash tables > than your memory can hold (not that difficult). Well, I didn't even for a second consider the possibility of holding all the data in memory. Whatever the storage architecture is I'm assuming the data is in a database a-la MySQL, even if it's just a long list of triplets. > The only way to have an efficient and still powerful storage engine is > to mix standards. For very local queries, hashes can be a good solution. > For locally distributed queries, lists and binary indexes might perform > better. But for truly distributed queries (outside of your domain) you > need an adaptive indexing system. > The more distributed you go slower it is, but that's acceptable when you > reckon the quality of your data will be higher that way. What do you mean with local/distributed queries? The use I have in mind is local to a company but geographically distributed because the company has facilities in various continents. > More alternatives than standards... see the Wiki pages to learn more: > http://esw.w3.org/topic/FrontPage > http://esw.w3.org/topic/SemanticWebTools > http://esw.w3.org/topic/CommercialProducts > http://esw.w3.org/topic/Semantic_Bioinformatics (storage at the end) Thank you, I'll check them out! Ciao! Manu
Received on Wednesday, 26 September 2007 11:33:33 UTC