| s | p_blank | o_blank |
|---|---|---|
| /id/statistical-geography/S01002000 | http://www.w3.org/1999/02/22-rdf-syntax-ns#type | geosparql: Geometry |
| /id/statistical-geography/S01002000 | geosparql: asWKT | POLYGON ((-3.111516726670726 55.93613468505033, -3.114669285918472 55.936114215000416, -3.113625047113639 55.93548588635172, -3.11456668839138 55.935387515264416, -3.114296971205442 55.93435663397815, -3.115015312255131 55.934287235444884, -3.115401462827867 55.93546981284777, -3.116239858044207 55.935677867665916, -3.117095272366098 55.93536460884822, -3.117826305308741 55.935735363896875, -3.118650477351612 55.935449333979335, -3.118595315559546 55.936312434162, -3.114879013126157 55.936229316746214, -3.115075188872918 55.93915678202771, -3.114402676960795 55.93919627213827, -3.113996357417153 55.940056097693365, -3.112190552011651 55.94017125459919, -3.112065299825468 55.93895485258336, -3.109256007547277 55.939381234971755, -3.11080665527009 55.93712870720871, -3.109446790488605 55.93715893372087, -3.10958757105322 55.93648376086302, -3.111478894205406 55.936565548394114, -3.111516726670726 55.93613468505033)) |
The most flexible way to access the data is by using SPARQL, a query language, analagous to SQL for relational databases, for retrieving and manipulating data from graph databases like ours. We support SPARQL 1.1 query syntax. Many online tutorials are available.
To submit a SPARQL query from your code, you issue an HTTP GET or POST to our endpoint:http://statistics.gov.scot/sparql, with the query itself as a url-encoded parameter called query.
For example, to run the following simple SPARQL query and get the results as JSON:
SELECT * WHERE {?s ?p ?o} LIMIT 10Issue a POST to the endpoint, with the query in the body, and an Accept header of sparql-results+json:
POST http://statistics.gov.scot/sparql HTTP/1.1
Host: statistics.gov.scot
Accept: application/sparql-results+json
Content-Type: application/x-www-form-urlencoded
query=SELECT+%2A+WHERE+%7B%3Fs+%3Fp+%3Fo%7D+LIMIT+10Issue a GET to the following URL (note the .json extension - see the formats section for more detail on this):
GET http://statistics.gov.scot/sparql.json?query=SELECT+%2A+WHERE+%7B%3Fs+%3Fp+%3Fo%7D+LIMIT+10Scroll down to the end of this page for examples of both of these methods in a few different languages.
As with other aspects of our API, to get the data in different formats, you can use either (a) a format extension or (b) an HTTP Accept header. Available result formats depend on the type of SPARQL query. There are four main forms:
SELECT queries return tabular results, and the formats available reflect this:
| Format | Extensions | Accept Headers |
|---|---|---|
| XML | .xml |
application/xml, application/sparql-results+xml |
| JSON | .json |
application/json, application/sparql-results+json |
| Text | .txt, .text | text/plain |
| CSV | .csv | text/csv |
CONSTRUCT and DESCRIBE queries return graph data, so the results are available in the same formats as our resource APIs:
| Format | Extensions | Accept Headers |
|---|---|---|
| RDF/XML | .rdf | application/rdf+xml |
| N-triples | .nt, .txt, .text | application/n-triples, text/plain |
| Turtle | .ttl | text/turtle |
| JSON-LD | .json | application/ld+json, application/json |
ASK queries return a boolean result:
| Format | Extensions | Accept Headers |
|---|---|---|
| XML | .xml | application/xml, application/sparql-results+xml |
| JSON | .json | application/json, application/sparql-results+json |
| Text | .txt, .text | text/plain |
We accept page and per_page parameters for paginating the results of SELECT queries (we automatically modify your query to apply LIMIT and OFFSET clauses). For other query types (i.e. DESCRIBE, CONSTRUCT, ASK), pagination like this doesn’t make so much sense, so these parameters are ignored.
For requests made through the website (i.e. HTML format), the page size is defaulted to 20. For requests to our sparql endpoint for data formats (i.e. non-HTML), there will be no defaults for these parameters (i.e. results are unlimited. For performance reasons we generally advise LIMITing your query if possible).
You can parameterise your SPARQL by including %{tokens} in your queries, and providing values for the tokens in the request parameters.
Note that the following tokens are reserved and cannot be used as parameters for substitution:
controlleractionpageper_pageidcommitutf8queryOur servers are configured to allow access from all domains. This means that if you’re writing JavaScript to request data from our server in to a web page hosted on another domain, your browser should check this header and allow it.
If you need to support very old browsers, you can additionally pass a callback parameter and the results will be wrapped in that function. For example:
http://statistics.gov.scot/sparql.json?callback=myCallbackFunction&query=SELECT+%2A+WHERE+%7B%3Fs+%3Fp+%3Fo%7D+LIMIT+10This help topic on the jQuery website has more details.
Here’s a couple of examples running a query using the widely available cURL command line program.
Request the results as XML, using a POST:
curl -X POST -H "Accept: application/sparql-results+xml" -d "query=SELECT%20*%20WHERE%20%7B%3Fs%20%3Fp%20%3Fo%7D%20LIMIT%2010" http://statistics.gov.scot/sparqlRequest the results as JSON, using a GET:
curl -X GET -H "Accept: application/sparql-results+json" http://statistics.gov.scot/sparql?query=SELECT%20*%20WHERE%20%7B%3Fs%20%3Fp%20%3Fo%7D%20LIMIT%2010This example HTML page uses jQuery to issue a POST to our SPARQL endpoint, requesting the results as JSON.
<!DOCTYPE html>
<html lang='en'>
<head>
<script src='http://code.jquery.com/jquery-1.9.1.min.js'></script>
</head>
<body>
<script type='text/javascript'>
var query = 'SELECT * WHERE {?s ?p ?o} LIMIT 10';
var url = 'http://statistics.gov.scot/sparql.json';
$.ajax({
method: 'POST',
dataType: 'json',
url: url,
data: {query: query},
success: function(data) {
alert('success: ' + data.results.bindings.length + ' results');
console.log(data);
}
});
</script>
</body>
</html>