15:59:29 <RRSAgent> RRSAgent has joined #rdb2rdf
15:59:29 <RRSAgent> logging to http://www.w3.org/2010/07/27-rdb2rdf-irc
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15:59:48 <Ashok> zakim, this is rdb2rdf
15:59:48 <Zakim> ok, Ashok; that matches SW_RDB2RDF()12:00PM
16:00:01 <Ashok> chair: Ashok
16:00:14 <Ashok> meeting:  RDB2RDF
16:00:33 <Zakim> +[IPcaller.aa]
16:00:59 <Zakim> +Ashok_Malhotra
16:01:47 <Seema> Seema has joined #rdb2rdf
16:02:22 <Zakim> +OpenLink_Software
16:02:26 <ericP> Zakim, please dial ericP-office
16:02:26 <Zakim> ok, ericP; the call is being made
16:02:27 <Zakim> +EricP
16:02:30 <MacTed> Zakim, OpenLink_Software is temporarily me
16:02:30 <Zakim> +MacTed; got it
16:02:42 <MacTed> Zakim, who's here?
16:02:42 <Zakim> On the phone I see [IPcaller], [IPcaller.a], [IPcaller.aa], Ashok_Malhotra, MacTed, EricP
16:02:44 <Zakim> On IRC I see Seema, nunolopes, RRSAgent, Zakim, boris, Ashok, alexdeleon, juansequeda, MacTed, LeeF, cygri, iv_an_ru, ericP, trackbot
16:02:50 <Zakim> +seema
16:03:32 <ericP> scriebick: ericP
16:03:35 <ericP> scriebic: ericP
16:03:47 <MacTed> scribenic: ericP
16:03:55 <MacTed> scribenick: ericP
16:03:57 <Ashok> scribe: ericP
16:04:09 <Souri> Souri has joined #rdb2rdf
16:04:12 <ericP> scrb: ericP (the unix version)
16:04:31 <Zakim> +Souri
16:04:33 <Ashok> Topic: Accept the minutes of last meeting, see http://www.w3.org/2010/07/20-rdb2rdf-minutes.html 
16:04:52 <ericP> RESOLVED: approve http://www.w3.org/2010/07/20-rdb2rdf-minutes
16:05:39 <juansequeda> Slides: http://www.slideshare.net/alexmiller/revelytix-rdb2rdf
16:05:49 <Ashok> Topic:  Presentation by Alex Miller http://www.slideshare.net/alexmiller/revelytix-rdb2rdf
16:06:25 <ericP> -> http://www.slideshare.net/alexmiller/revelytix-rdb2rdf Presentation by Alex Miller
16:06:31 <cygri_> cygri_ has joined #rdb2rdf
16:07:00 <Ashok> zakim, who is on the phone?
16:07:00 <Zakim> On the phone I see [IPcaller], [IPcaller.a], [IPcaller.aa], Ashok_Malhotra, MacTed, EricP, seema, Souri
16:07:22 <ericP> alexdeleon: implemented a federating relational query engine
16:07:37 <ericP> ... worked in XML, XQuery, non-relational systems
16:07:43 <Ashok> present: Souri, Seema, Ashok, EricP, Juan, MacTed
16:08:02 <Ashok> Please enter your attendance if 
16:08:17 <ericP> ... working in semantic domain at Revelytix
16:08:23 <Zakim> +mhausenblas
16:08:35 <Ashok> ... I missed you like this:  present+:yourname
16:08:52 <ericP> ... working with DOD for cross-domain queries
16:08:56 <cygri> zakim, mhausenblas is cygri
16:08:56 <Zakim> +cygri; got it
16:08:58 <ericP> [slide 3
16:09:00 <ericP> ]
16:09:06 <cygri> zakim, nunolopes is with cygri
16:09:06 <Zakim> +nunolopes; got it
16:09:12 <cygri> zakim, boris is with cygri
16:09:12 <Zakim> +boris; got it
16:09:52 <Ashok> present+: cygri
16:09:58 <ericP> alexdeleon: Business Intellegence/federation are critical
16:10:26 <Ashok> present+: Boris
16:11:47 <cygri> strong +1 to everything on slide 3 from D2RQ experience
16:12:23 <ericP> alexdeleon: given an item in the domain ontology, what db contains it?
16:12:33 <juansequeda> ericP, alexdeleon is not Alex Miller
16:12:34 <ericP> ... if i change X, what will have to change
16:13:23 <Ashok> present+: LeeF
16:14:17 <ericP> ericP: when you say "mappings are useful artifacts", are you e.g. sharing the heads of the rules to target federated queries?
16:14:21 <Marcelo> Marcelo has joined #rdb2rdf
16:14:27 <ericP> alexmiller: not yet, but sounds reasonable
16:14:36 <ericP> [slide 4]
16:14:42 <Ashok> present+: Marcelo
16:15:18 <Zakim> +Marcelo
16:15:34 <ericP> alexmiller: domain ontologists tend to work on the schema before they have access to the mapping
16:15:41 <Marcelo> Sorry, I was in a meeting.
16:17:29 <ericP> alexmiller: we built some closed-world validation tools
16:17:43 <ericP> ... started with SPARQL queries, but that left things we couldn't check for
16:18:00 <ericP> ... found C&P's talk at SemTech interesting
16:19:14 <ericP> ... we decided to try our own mapping language
16:19:35 <ericP> ... led us to furthur respect d2r
16:19:59 <ericP> ... tx to juansequeda for comparing approaches
16:20:05 <ericP> [slide 5]
16:20:49 <ericP> alexmiller: still working on atomicity of mapping operators
16:21:41 <ericP> ... pattern concept similar to the strings in d2r
16:21:58 <ericP> ... looking for a more flexible way to plug into patterns
16:22:10 <ericP> ... ended up being very verbose
16:22:16 <ericP> [slide 6]
16:22:25 <Ashok> present+: Ivan
16:22:47 <ericP> alexmiller: we view mappings as producing triples
16:23:01 <Marcelo> Where can I find the slides?
16:23:05 <ericP> ... each mapping has two phases:
16:23:08 <Ashok> present+: NunoLopes
16:23:25 <ericP> ... .. pull from the data store to produce tuples
16:23:31 <Ashok> Presentation by Alex Miller http://www.slideshare.net/alexmiller/revelytix-rdb2rdf
16:23:38 <ericP> ... .. the SPO specifies the shape of the output
16:23:54 <Marcelo> Thanks!
16:24:10 <ericP> ... in Revelytix, you can use one map to refine another
16:24:25 <ericP> ... e.g. base a propertyMap off another propertyMap
16:24:48 <ericP> [slide 7]
16:25:24 <ericP> alexmiller: of a SQL query appear
16:25:48 <ericP> alexmiller: all the parts of an SQL query appear
16:26:11 <ericP> ... a propertyMap based on a classMap will inherit the classMap's subject
16:26:51 <ericP> ... build upon a base uri
16:27:22 <ericP> ... didn't get as far as we hoped. big tension between brevity and flexibility
16:27:46 <ericP> [slide 12]
16:28:16 <ericP> alexmiller: case0 produces rdf:type triples
16:29:55 <ericP> ... { <http://.../student/#Students<s_id>> a ex:Student }
16:30:14 <ericP> Ashok: could you draw on multiple sql tables?
16:30:32 <ericP> alexmiller: yes, any SQL. also possible with a property path
16:30:43 <ericP> ... also worked on an ontology to represent a database
16:31:07 <ericP> ... built something that generates an ontology with all the tables, keys, etc.
16:31:35 <ericP> ... useful to ontologists who can refer to db parts by URI
16:31:49 <ericP> ... also links database ontology and domain ontology
16:32:14 <ericP> juansequeda: what exactly generates the ontologies?
16:32:34 <ericP> alexmiller: we have an oltology to represent it and some tools to populate it
16:32:40 <ericP> ... uses jdbc, etc.
16:32:52 <ericP> [slide 13]
16:33:07 <ericP> alexmiller: propertyMap inherits from classMap
16:34:05 <ericP> ... { <http://.../student/#Students<s_id>> foaf:name {.name} }
16:34:15 <ericP> Ashok: could you embed functions?
16:34:44 <ericP> alexmiller: yes, need to assign to a literal and do functions on that
16:35:14 <ericP> ... we defined our SQL, close to '92 or '08.
16:35:43 <ericP> ... functions were problematic; jdbc/odbc standard functions don't match SQL standard functions
16:35:52 <ericP> ... drivers add their own functions
16:36:02 <ericP> ... we tried to support a superset
16:36:27 <ericP> ... not sure it's appropriate for you, but it worked for us
16:37:16 <ericP> ... OUTER JOIN syntax was pretty hairy
16:37:33 <Ashok> Eric:  Is yr goal to take a SPARQL query and translate to a single SQL query?
16:38:43 <ericP> ... we were unable to push some user-defined functions to the source
16:39:26 <ericP> ... often hard to compute the inverse of functions. e.g. aritmetic fucntions, to push to client
16:40:15 <ericP> ... we document the capabilities of a source; we support the complement in the engine
16:40:49 <ericP> [slide 14]
16:42:17 <ericP> alexmiller: i liked virtuoso's URI templates based on [db] keys
16:42:44 <ericP> juansequeda: so in d2rq, you have to write the join, but in your's, you don't?
16:42:51 <ericP> alexmiller: yeah, that's about right
16:43:23 <ericP> ... the mapping of foreign keys to primary keys allows us to compose the joins
16:44:02 <ericP> ... i want to re-use the info in the well-normalized schemas 
16:45:00 <ericP> ericP: is it acceptable to have a tool interrogate the constraints and generate a configuration?
16:45:24 <ericP> alexmiller: yes, we provide a default mapping, which you are free[/encouraged] to extend
16:47:13 <ericP> juansequeda: so an ontologist will be working with the schema, but a user more familiar with SQL would be driving it by join constraints?
16:47:20 <ericP> alexmiller: pretty much
16:47:30 <ericP> RRSAgent, please draft minutes
16:47:30 <RRSAgent> I have made the request to generate http://www.w3.org/2010/07/27-rdb2rdf-minutes.html ericP
16:48:09 <ericP> juansequeda: how much optimization do you do in the query generation vs. leting the SQL engine do it?
16:48:59 <ericP> alexmiller: ideally, we'd just push it down, but we're all aware that we need to take advantage of the schema and write efficient queries
16:49:16 <ericP> cygri: per slide 4, you said "SQL in strings is a bad thing"
16:50:01 <Ashok> rrsagent, make logs public
16:50:02 <ericP> ... you avoid it in Revelytix by having an ontology which names the elements in the database? what's the advantave?
16:50:19 <ericP> alexmiller: easier to validate using existing SemWeb tools
16:50:46 <ericP> ... but it has its own set of issues; i'm not saying it's the ultimate solution
16:51:49 <ericP> scribenick: Ashok 
16:53:22 <Ashok> Richard:  Outlines RDB2RDF approach 
16:53:48 <Ashok> Alex:  Makes sense ... we want to be mapping language agnostic
16:55:04 <Zakim> -EricP
16:55:40 <Ashok> Richard:  Could we see example of ontology for db schema?
16:55:57 <Ashok> Alex:  I will send something
17:01:43 <Zakim> -Souri
17:01:44 <Zakim> -seema
17:01:45 <Zakim> -[IPcaller.a]
17:01:52 <Zakim> -cygri
17:01:55 <Zakim> -[IPcaller.aa]
17:01:57 <Zakim> -[IPcaller]
17:01:59 <Zakim> -Ashok_Malhotra
17:01:59 <Ashok> Juan:  Marcelo can stert work on a semantics document
17:02:01 <Zakim> -Marcelo
17:02:03 <Zakim> -MacTed
17:02:05 <Zakim> SW_RDB2RDF()12:00PM has ended
17:02:07 <Zakim> Attendees were [IPcaller], Ashok_Malhotra, EricP, MacTed, seema, Souri, cygri, nunolopes, boris, Marcelo
17:02:52 <Ashok> s/Marcelo/Marcelo and I/
17:03:01 <nunolopes> nunolopes has joined #RDB2RDF
17:03:07 <Ashok> ... discussion of form of the document.
17:03:17 <Ashok> ... Let's start with a Wiki
17:03:29 <Ashok> rrsagent, draft minutes
17:03:29 <RRSAgent> I have made the request to generate http://www.w3.org/2010/07/27-rdb2rdf-minutes.html Ashok
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