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Stuart, This presentation was given at the Code4Lib conference in 2009. It is a good starting point. http://www.slideshare.net/iandavis/30-minute-guide-to-rdf-and-linked-data I will dig around and try to find some other presentations or documents/articles that could be a used for introductory purposes. Thanks, Jeff Mixter Research Support Specialist OCLC Research 614-761-5159 [log in to unmask] ________________________________________ From: Code for Libraries <[log in to unmask]> on behalf of Forrest, Stuart <[log in to unmask]> Sent: Friday, December 19, 2014 2:38 PM To: [log in to unmask] Subject: Re: [CODE4LIB] rdf triplestores This all sounds really interesting, can anyone recommend a resource for learning what it's all about and what it can be used for? Stuart =============================================================================== Stuart Forrest PhD Library Systems Specialist Beaufort County Library 843 255 6450 [log in to unmask] http://www.beaufortcountylibrary.org For Leisure, For Learning, For Life -----Original Message----- From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of Hugh Cayless Sent: Friday, December 19, 2014 2:29 PM To: [log in to unmask] Subject: Re: [CODE4LIB] rdf triplestores That's pretty much it. There are operations that are completely natural to a graph db that require either many joins or multiple queries to achieve with an RDBMS. It all depends very much on what sorts of data you're dealing with, and how you want to model that data. Graph databases can certainly be faster/more efficient at querying data with many joins than RDBMSs are. It's (unsurprisingly) easier to model data that looks like a web of relationships in a graph db than in an RDBMS. They're not so great at dealing with regular, record-shaped data on the other hand, nor document-shaped data for that matter. They are a very useful tool to have in your kit and using them will likely change the way you think about data modeling in a good way. On Fri, Dec 19, 2014 at 2:05 PM, Sarah Weissman <[log in to unmask]> wrote: > > Jeff, > > > > With graph data it is much easier to search for an author (lets say > > Jane > > Austen) and find not only all of the books that she authored but > > also all of the books about her, all of the books that are about > > similar topics, published in similar periods. One can then imaging > > hopping from the Jane Austen node on the graph to a node that is a > > book she wrote (say Pride > and > > Prejudice) and then to a subject node for the book (say "Social > > Classes--Fiction). From there you could then find all of the Authors > > that wrote books about that same topic and then navigate to those books. > > > > > When you say that it would be "easier" to discover these other > relations from the Jane Austen node, do you mean that you can query > for relations in a triplestore/graph DB more readily (efficiently?) than you can in a RDB? > It seems like the equivalent in the RDB model would be, given a piece > of data used in a FK column in a table, to query for (if you even > could) what other tables use the same FK, then query these tables, > constraining to the Jane Austen value to see whether or not they had > any data, which is not a "natural" way of using a RDB. > > -Sarah > > > On Fri, Dec 19, 2014 at 11:10 AM, Mixter,Jeff <[log in to unmask]> wrote: > > > Stuart, > > > > Since triplestores, in essence, store graph data I think a slightly > better > > question is what can you do with graph data (if you do not mind me > > rephrasing you question). > > > > From this perspective I would point to Facebook or LinkedIn as prime > > examples of what can be done with graph data. Obviously those do not > > necessarily translate well into what can be done with library graph > > data but it does show the potential. For libraries, I think one of > > the > benefits > > will be expanded/enhanced discoverability for resources. > > > > With graph data it is much easier to search for an author (lets say > > Jane > > Austen) and find not only all of the books that she authored but > > also all of the books about her, all of the books that are about > > similar topics, published in similar periods. One can then imaging > > hopping from the Jane Austen node on the graph to a node that is a > > book she wrote (say Pride > and > > Prejudice) and then to a subject node for the book (say "Social > > Classes--Fiction). From there you could then find all of the Authors > > that wrote books about that same topic and then navigate to those books. > > > > Our current ILS systems try t o do this with MARC records but > > because > they > > are mostly string based, it is very difficult to accurately provide > > this type of information to users. Graph data helps overcome this hurdle. > > > > This was a rather basic example of how end-users can benefit from > > graph data but I think it is a compelling reason. > > > > I have attached a simple image to help visualize what I was talking > about. > > In it the user would start by finding Author1 and then using the > > graph we (the library) could suggest that they might like Book2 > > (since it is about the same subject) or even Book3 (since it is by > > Author2 who wrote a book, Book2, that shared a common subject, > > Subject1, with the author, Author1, that was originally searched > > for. Again, this is very basic but would be rather difficult to do with a string base record system. > > > > If you wanted to add complexity, you could start talking about > > discover > of > > multi-lingual items for bilingual users (since graph data should be > > language neutral). > > > > Thanks, > > > > Jeff Mixter > > Research Support Specialist > > OCLC Research > > 614-761-5159 > > [log in to unmask] > > > > ________________________________________ > > From: Code for Libraries <[log in to unmask]> on behalf of > Forrest, > > Stuart <[log in to unmask]> > > Sent: Friday, December 19, 2014 10:32 AM > > To: [log in to unmask] > > Subject: Re: [CODE4LIB] rdf triplestores > > > > Thanks Jeff > > > > Interesting concept, can you give me any examples of their usage, > > what kinds of data etc.? > > > > Thanks > > > > > > > ====================================================================== > ========== > > Stuart Forrest PhD > > Library Systems Specialist > > Beaufort County Library > > 843 255 6450 > > [log in to unmask] > > > > http://www.beaufortcountylibrary.org > > > > For Leisure, For Learning, For Life > > > > > > > > > > -----Original Message----- > > From: Code for Libraries [mailto:[log in to unmask]] On Behalf > > Of Mixter,Jeff > > Sent: Friday, December 19, 2014 10:20 AM > > To: [log in to unmask] > > Subject: Re: [CODE4LIB] rdf triplestores > > > > A triplestore is basically a database backend for RDF triples. The > > major benefit is that it allows for SPARQL querying. You could > > imagine a triplestore as being the same thing as a relational > > database that can be queried with SQL. > > > > The drawback that I have run into is that unless you have unlimited > > hardware, triplestores can run into scaling problems (when you are > looking > > at hundreds of millions or billions of triples). This is a problem > > when > you > > want to search for data. For searching I use a hybrid Elasticsearch (i.e. > > Lucene) index for the string literals and the go out to the > > triplestore > to > > query for the data. > > > > If you are looking to use a triplestore it is important to > > distinguish between search and query. > > > > Triplestore are really good for query but not so good for search. > > The basic problem with search is that is it mostly string based and > > this requires a regular expression query in SPARQL which is > > expensive from a hardware perspective. > > > > There are a few triple stores that use a hybrid model. In particular > > Jena Fuseki > > (http://jena.apache.org/documentation/query/text-query.html) > > > > Thanks, > > > > Jeff Mixter > > Research Support Specialist > > OCLC Research > > 614-761-5159 > > [log in to unmask] > > > > ________________________________________ > > From: Code for Libraries <[log in to unmask]> on behalf of > Forrest, > > Stuart <[log in to unmask]> > > Sent: Friday, December 19, 2014 10:00 AM > > To: [log in to unmask] > > Subject: Re: [CODE4LIB] rdf triplestores > > > > Hi All > > > > My question is what do you guys use triplestores for? > > > > Thanks > > Stuart > > > > > > > > > ====================================================================== > ========== > > Stuart Forrest PhD > > Library Systems Specialist > > Beaufort County Library > > 843 255 6450 > > [log in to unmask] > > > > http://www.beaufortcountylibrary.org > > > > For Leisure, For Learning, For Life > > > > > > > > -----Original Message----- > > From: Code for Libraries [mailto:[log in to unmask]] On Behalf > > Of Stefano Bargioni > > Sent: Monday, November 11, 2013 8:53 AM > > To: [log in to unmask] > > Subject: Re: [CODE4LIB] rdf triplestores > > > > My +1 for Joseki. > > sb > > > > On 11/nov/2013, at 06.12, Eric Lease Morgan wrote: > > > > > What is your favorite RDF triplestore? > > > > > > I am able to convert numerous library-related metadata formats > > > into > > RDF/XML. In a minimal way, I can then contribute to the Semantic Web > > by simply putting the resulting files on an HTTP file system. But if > > I were > to > > import my RDF/XML into a triplestore, then I could do a lot more. > > Jena seems like a good option. So does Openlink Virtuoso. > > > > > > What experience do y'all have with these tools, and do you know > > > how to > > import RDF/XML into them? > > > > > > -- > > > Eric Lease Morgan > > > > > >