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From jpz6311...@apache.org
Subject svn commit: r1614863 - in /jena/site/trunk/content/documentation/csv: ./ index.mdtext
Date Thu, 31 Jul 2014 11:45:21 GMT
Author: jpz6311whu
Date: Thu Jul 31 11:45:20 2014
New Revision: 1614863

URL: http://svn.apache.org/r1614863
Log:
documentation for JENA-625

Added:
    jena/site/trunk/content/documentation/csv/
    jena/site/trunk/content/documentation/csv/index.mdtext

Added: jena/site/trunk/content/documentation/csv/index.mdtext
URL: http://svn.apache.org/viewvc/jena/site/trunk/content/documentation/csv/index.mdtext?rev=1614863&view=auto
==============================================================================
--- jena/site/trunk/content/documentation/csv/index.mdtext (added)
+++ jena/site/trunk/content/documentation/csv/index.mdtext Thu Jul 31 11:45:20 2014
@@ -0,0 +1,55 @@
+Title: CSV PropertyTable
+
+This module is about getting CSVs into a form that is amenable to Jena SPARQL processing,
and doing so in a way that is not specific to CSV files. 
+It includes getting the right architecture in place for regular table shaped data, using
the core abstraction of PropertyTable.
+
+*Illustration*
+
+This module involves the basic mapping of CSV to RDF using a fixed algorithm, including interpreting
data as numbers or strings.
+
+Suppose we have a CSV file located in ¡°file:///c:/town.csv¡±, which has one header row,
two data rows:
+
+    Town,Population
+    Southton,123000
+    Northville,654000
+ 
+As RDF this might be viewable as:
+ 
+    @prefix : <file:///c:/town.csv#> .
+    @prefix csv: <http://w3c/future-csv-vocab/> .
+    [ csv:row 1 ; :Town "Southton" ; :Population  ¡°123000¡±^^http://www.w3.org/2001/XMLSchema#int
] .
+    [ csv:row 2 ; :Town "Northville" ; :Population  ¡°654000¡±^^http://www.w3.org/2001/XMLSchema#int
 ] .
+ 
+or without the bnode abbreviation:
+ 
+    @prefix : <file:///c:/town.csv#> .
+    @prefix csv: <http://w3c/future-csv-vocab/> .
+    _:b0  csv:row 1 ;
+          :Town "Southton" ;
+          :Population ¡°123000¡±^^http://www.w3.org/2001/XMLSchema#int .
+    _:b1  csv:row 2 ;
+          :Town "Northville" ;
+          :Population ¡°654000¡±^^http://www.w3.org/2001/XMLSchema#int.
+          
+Each row is modeling one "entity" (here, a population observation). 
+There is a subject (a blank node) and one predicate-value for each cell of the row. 
+Row numbers are added because it can be important. 
+Now the CSV file is viewed as a graph - normal, unmodified SPARQL can be used. 
+Multiple CSVs files can be multiple graphs in one dataset to give query across different
data sources.
+ 
+We can use the following SPARQL query for ¡°Towns over 500,000 people¡± mentioned in
the CSV file:
+ 
+    SELECT ?townName ?pop {
+      GRAPH <file:///c:/town.csv> {
+        ?x :Town ?townName ;
+           :Popuation ?pop .
+        FILTER(?pop > 500000)
+      }
+    }
+
+## Get Started
+
+## Design
+
+## Implementation
+



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