This SPARQL update query reconstructs links between sample assessment records after publishing or removing data. It first deletes existing "replaces" and "isReplacedBy" links. It then inserts new links, finding an update record and predecessor based on replacement/withdrawal status and date. It ensures there is no sample between the update and predecessor.

1. Linked Environmental Data
Alex Coley @alexrcoley
Stuart Williams @skwlilac

2. rationale
Alex

3. our vision
a better
place for
people and
wildlife
to achieve this we will
Act to reduce Work with
Protect and Work with people
climate change businesses and other
improve water, and communities to
and its organisations to use
land and air create better places
consequences resources wisely
Be the best we
can
We cannot do this alone. We work closely with a wide range of
partners including government, business, local authorities, other
agencies, civil society groups and the communities we serve.

4. how we used to supply data
EA hosted web services
(and very restricted access to the actual data)
data supplies &
information requests

5. INSPIRE
Infrastructure for Spatial Information in
the European Community

6. bathing water quality
start of season
Press interest
15th May
bathing season
20-22 samples
what information in 22weeks
is relevant to the public
about beaches 30th Sept
annual report
November
what
we do December

7. Proof of concept (one off)
Pilot
BAU and extend

8. defining things (and context)

9. why Linked data
Alex

11. Tenby
Tourist Information Centre
Unit 2 , The Gateway Complex
Tenby. Wales , SA70 7LT
Tel: 01834 842 402
Fax: 01834 845 439
Email: tenby.tic@pembrokeshire.gov.uk
Photo by Skellig2008 (flickr)

12. Day 1 Day 1-3 Day 4
entered onto monitoring /
operational database
Sampling happens Lab analysis happens
Tuesday (snapshot)
available via data.gov.uk
Bathing Water
Weekly/Daily
assessment run
available on WIYBY
Linked data
“feeds” available on EyeOnEarth
available on our own apps
available on other apps

13. more than ‘just’ linked data
api configuration *
applications
update process
data modelling
additional data
mini apps
* api as organised URI space
with consistent behaviours documentation others apps

15. practical issues
Stuart

16. URIs + Governance
Stable points of reference
Applications
Operational Data
Domain
Reference Data
Vocabularies
Standard
Vocabularies (RDF, RDFS, OWL)
Vocabularies and Reference Data form the foundations
Image from Wikimedia Commons CC-BY-2.5

17. "Cool URI's don't change" but...
http://www.w3.org/Provider/Style/URI
Stakeholder URI Sets
Sector Governance
education school
transport station
environment bathing-water
... ...
http://{sector}.data.gov.uk/id/{concept}/{reference}
thematic code-point
id things
doc documents about things <- reference data
data datasets and data items
INSPIRE
def vocabularies and terms
so spatial object
Infrastructure for Spatial Information in
the European Community

18. URI Space Map

19. Modelling
• Access to Domain Expertise (not just data)
• Linkage to Legislation (terms and definitions)
• Entities and Relationships
• Lifecycles
• Mutable and Invariant Properties
• Sameness and difference
• What do things mean?
• eg. Assessment Criteria
• Code lists (G,I,F,C,N what do these mean?)

20. Revising Sample Assessments
http://environment.data.gov.uk/data/bathing-water-quality/in-season/sample/point{bwspid}/date/{sampleDate}/time/{sampleTime}/recordDate/{recordDate}
bwq:recordDate bwq:recordStatus
2011-08-01 bwq:new
dct:replaces dct:isReplacedBy
2011-08-04 bwq:replacement
dct:replaces dct:isReplacedBy
2011-08-08 bwq:replacement
dct:replaces dct:isReplacedBy
2011-08-11 bwq:withdrawal
recordStatus new -> replacement -> withdrawn
replaces / isReplaced linkages maintained using SPARQL Update.

21. Scaling Up
Update Server
Load
Balancers
SPARQL Update
Upload
Preview /
Convert
Review
Publish /
Remove
(Disposable)
Publishing
Backup / Restore Server x N

22. Encouraging Use and Reuse
RESTful API
http://environment.data.gov.uk/id/bathing-water/ukc2102-03600
http://environment.data.gov.uk/id/bathing-water
SELECT ?item
View Control WHERE { ... }
&view= selector Data
&_property={properties} GET /doc/bathing-water Store
&_metadata= +
viewer
DESCRIBE SPARQL
Page Control <x> <y> ... <z> Endpoint
&page= formatter
Formatted Response
&pageSize=
'native' linked data RDF Endpoint
semantic web TTL
Filtering
CSV
&{property}={value} Publication Server
'Developer friendly' XML config
&min-{property}={value} (elda+fuseki+jena)
JSON
&max-{property}={value}
Styled data for people HTML
Misc.
&_sort=
&_lang={langTags}
&callback= (for JSONP) Apache Jena

23. Encouraging Use & Reuse
Developer Friendly Formats

24. Encouraging Use & Reuse
Documentation
Data Model and
API URI pattern Reference
http://environment.data.gov.uk/lab/

25. Rich Web Applications...
English Welsh

26. Embeddable Widgets and Mobile Apps

27. where next
Alex

28. Our data and information
will be usable and useful to
whoever needs to use it

29. BW
Rivers
Profile
Bathing
Water WFD
public
record
Reference
Flood
Linked Data
Linked Services
Internal

30. Questions…
Alex and Stuart

31. Alex Coley
@alexrcoley
alex.coley@environment-agency.gov.uk
www.environment-agency.gov.uk
environment.data.gov.uk
Stuart Williams
@skwlilac
skw@epimorphics.com data.gov.uk/linked-data
www. epimorphics.com

33. SPARQL Update Query (part 1 of 3)
preamble and delete
# SPARQL update query to patch up store after a publish or remove
PREFIX qb: <http://purl.org/linked-data/cube#>
PREFIX bwq: <http://environment.data.gov.uk/def/bathing-water-quality/>
PREFIX dct: <http://purl.org/dc/terms/>
PREFIX interval: <http://reference.data.gov.uk/def/intervals/>
# Remove previous replaces/replacedBy links for records
DELETE {
?update dct:replaces ?predecessor .
?predecessor dct:isReplacedBy ?update . }
WHERE {
?update dct:replaces ?predecessor .
?predecessor dct:isReplacedBy ?update . } ;

34. SPARQL Update Query (part 2 of 3)
insert: find an update record and its predecessors
# Reconstruct links based on current replacements/withdrawals
INSERT {
?update dct:replaces ?predecessor .
?predecessor dct:isReplacedBy ?update . }
WHERE {
?update a bwq:SampleAssessment;
bwq:bathingWater ?bw;
bwq:samplingPoint ?sp;
bwq:sampleDateTime ?u_stime ;
bwq:recordDate ?u_recordDate;
{ ?update bwq:recordStatus ?bwq:withdrawal }
UNION
{ ?update bwq:recordStatus ?bwq:replacement }
# Find a ?prececessor
?predecessor a bwq:SampleAssessment;
bwq:bathingWater ?bw;
bwq:samplingPoint ?sp;
bwq:sampleDateTime ?u_stime;
bwq:recordDate ?pred_recordDate;
.
FILTER (?pred_recordDate<?u_recordDate)

35. SPARQL Update Query (part 3 of 3)
insert: ensure there is no matching ?probe between ?update and ?predecessor
# Make sure that the is no ?probe between ?update and its immediate
# predecessor.
OPTIONAL {
?probe a bwq:SampleAssessment;
bwq:bathingWater ?bw;
bwq:samplingPoint ?sp;
bwq:sampleDateTime ?u_stime;
bwq:recordDate ?probe_recordDate;
FILTER ( ?probe_recordDate > ?pred_recordDate &&
?u_recordDate > ?probe_recordDate)
} FILTER (!bound(?probe))
} ;