This demo shows how many raw datasets have been contributed to Data.gov by each US government agency.
This demo queries the data.gov catalog
to list all the agencies that submitted data to data.gov, then counts the number of datasets each submitted. From the visualization, web users are presented with the following observations:
In this demo, SPARQL query results are displayed using various Google Visulization APIs including pie chart
, bar chart
, line chart
This demo also show the use of aggregation function in SPARQL (we used virtuoso syntax)
# this query used SPARQL 1.1 feature, and its SELECT clause is customized to virtuoso syntax
# we only query raw data catalog
PREFIX dgp92: <http://data-gov.tw.rpi.edu/vocab/p/92/>
SELECT ?agency , count(*) AS ?cnt
FROM NAMED <http://data-gov.tw.rpi.edu/raw/92/data-92.rdf>
?entry dgp92:agency ?agency.
?entry dgp92:data_gov_data_category_type "Raw Data Catalog" .
GROUP BY ?agency
ORDER BY DESC (?cnt )