Re: R2RML mappings of Non-unique Tables

On May 14, 2012, at 10:00 AM, David McNeil wrote:

> On Sun, May 13, 2012 at 12:20 PM, Eric Prud'hommeaux <eric@w3.org> wrote:
>> but that requires computing a query knowing the max cardinality.
>> 
>> Any idea where to go from here?
> 
> This query seems to work on PostgreSQL:
> 
> SELECT generate_series(1, count(*)), fname, lname, amount 
> FROM IOUs
> GROUP BY fname, lname, amount;

Sure, but note that the generate_series() function is special 
(unique?) to PostgreSQL.  

Most other engines require significant yak shaving for similar 
effect, and it may not be achievable with *every* other engine.

Ted



--
A: Yes.                      http://www.guckes.net/faq/attribution.html
| Q: Are you sure?
| | A: Because it reverses the logical flow of conversation.
| | | Q: Why is top posting frowned upon?

Ted Thibodeau, Jr.           //               voice +1-781-273-0900 x32
Senior Support & Evangelism  //        mailto:tthibodeau@openlinksw.com
                             //              http://twitter.com/TallTed
OpenLink Software, Inc.      //              http://www.openlinksw.com/
         10 Burlington Mall Road, Suite 265, Burlington MA 01803
     Weblog   -- http://www.openlinksw.com/blogs/
     LinkedIn -- http://www.linkedin.com/company/openlink-software/
     Twitter  -- http://twitter.com/OpenLink
     Google+  -- http://plus.google.com/100570109519069333827/
     Facebook -- http://www.facebook.com/OpenLinkSoftware
Universal Data Access, Integration, and Management Technology Providers