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14:58:40 <Ashok> meeting: RDB2RDF
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14:59:12 <Ashok> chair: Ashok
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15:06:08 <Ashok> scribenick: soeren
15:06:26 <Ashok> scribe Soeren Auer
15:07:40 <soeren> no objections for previous minutes
15:08:01 <soeren> oct30/31 will be f2f minute organized by wolfgang
15:08:11 <soeren> wolfgang will send more information
15:08:58 <soeren> no phone calls for next two weeks and no call 17th and 24th of Oct
15:10:04 <soeren> jenny green provided interesting use case scenario
15:10:33 <soeren> orri updated RDB2RDF requirements
15:10:53 <juansequeda> This is the link from Orri's updated requirement document: http://esw.w3.org/topic/Rdb2RdfXG/ReqForMappingByOErling
15:12:17 <soeren> discussion about Orri's requirements document
15:12:42 <soeren> Orri gives an introduction
15:16:07 <soeren> better definition of the scope of the requirements document
15:16:23 <soeren> addition of usages scenarios
15:16:47 <soeren> esp. with regard to mapping on demand
15:17:26 <soeren> some kind of basic inferencing is required
15:17:47 <soeren> e.g. when the same triples can be derived from different sources
15:19:07 <soeren> properties of mapping functions (injective, bijective etc) must be known by the mapping layer
15:22:30 <soeren> virtuoso provides some of the functionality already
15:23:21 <soeren> question from Ashok about Simplicity
15:23:44 <soeren> How can that be achieved?
15:24:05 <soeren> Orri answers: maybe by two language layers.
15:25:40 <soeren> often only few simple things are required
15:27:29 <soeren> Soeren: why not use SQL as a mapping language?
15:29:09 <Ashok> Ashok:  You can define a SQL query for each OWL class
15:30:30 <soeren> Orri will collect some examples of thnigs which are not easily expressible in SQL.
15:33:57 <Ashok> Jenny:  If you limit mapping to SQL you n only solve problems that SQL can solve
15:34:01 <soeren> Limitation to SQL can only problems that SQL can solve.
15:37:12 <soeren> Ashok: benefit of translating from RDB to RDF is integration of data, but the real value is when you can add extra semantic
15:38:08 <iv_an_ru_> +q
15:38:51 <soeren> Ivan: SPARQL is easier and simpler to write
15:39:23 <soeren> Jenny presents her use case:
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15:41:03 <soeren> create a demonstrator that takes spatial operations into account in RDF
15:41:17 <soeren> 5 different data sources from different companies
15:41:54 <soeren> questionnaires and knowledge elicitation techniques employed to create the data
15:42:45 <soeren> creation of ontologies for the datasources
15:42:58 <soeren> now merging of the ontologies and data sources
15:43:15 <Ashok> meeting: RDB2RDF
15:43:17 <soeren> spatial attributes hae to be considered
15:44:23 <soeren> SQUIRREL used for linking
15:44:55 <soeren> starting point are SPARQL queries
15:47:02 <soeren> one big table for polygons
15:47:47 <soeren> seven different conditions define what is a field, many different constraints on the metadata
15:48:45 <soeren> use of Oracle spatial operations
15:49:31 <soeren> D2RQ used for mapping
15:52:36 <soeren> no change of underlying data
15:53:23 <soeren> sometimes preprocessing required
15:54:01 <soeren> Orri: interesting use-case
15:54:51 <soeren> Ashok: Excellent use case since it speaks about data from multiple DBs and allows addition of semantics
15:55:25 <soeren> one more phone call till F2F
15:55:33 <soeren> 10th of October
15:56:00 <soeren> continuing discussion of Orri's requirements and Jenny's use case
15:56:27 <soeren> in the next conf. call
15:56:59 <soeren> Orri promises additions till next call
15:57:34 <Ashok> Adjourn
15:57:52 <Ashok> rrsagent, make logs public
15:58:10 <Ashok> rrsagent, create minutes
15:58:10 <RRSAgent> I have made the request to generate http://www.w3.org/2008/09/19-RDB2RDF-minutes.html Ashok
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