Presented at the Freebase NYC Workshop, December 2009. Covers basic MQL query construction, basic service calls and eMQL adapter construction. PHP Code can be found at http://dev.mqlx.com/~jamie/nyc2009

1. Freebase Workshop
Jamie Taylor
New York City, December 2009
Code available at: http://dev.mqlx.com/~jamie/nyc2009

2. Building a MQL Query

3. "type":"/type/object" is assumed
"name" = /type/object/name
[{
"name" : null,
"type" : "/tv/tv_program"
}]
MQL

4. http://www.freebase.com/app/queryeditor

5. {
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program"
}
MQL

7. "/program_creator" = /tv/tv_program/program_creator
{
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[ ]
}
MQL

8. {
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name":null }]
}
MQL

9. Mark Harmon
TV
Performance
Jethro Gibbs
{
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name:null }],
"regular_cast":[{
"actor":null,
"character":null
}]
}

10. {
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name:null }],
"regular_cast":[{
"actor":null,
"character":null
}]
}

11. Mark Harmon
TV
Performance
Jethro Gibbs
{
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name:null }],
"regular_cast":[{
"actor": {"id":null, "name":null},
"character":null
}]
}

12. {
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name:null }],
"regular_cast":[{
"actor": {"id":null, "name":null},
"character":null
}],
"spin_offs":[ ]
}

13. {
"id":"/en/ncis",
"name" : null,
"type" : "/tv/tv_program",
"program_creator":[{ "id":null, "name:null }],
"regular_cast":[{
"actor": {"id":null, "name":null},
"character":null
}],
"spin_offs":[{"id":null, "name":null,
"air_date_of_first_episode":null}]
}

14. Accessing Freebase Services
via PHP

15. Service Requests in PHP
• Using cURL to make external service requests
$topicid = "/en/ncis";
$widgeturl = "http://www.freebase.com/widget/topic?id=
$topicid&mode=i&panes=image,article_props";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $widgeturl);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$resultstr = curl_exec($ch);
curl_close($ch);
print $resultstr;

16. Accessing External Services
via MQL Extensions

17. A Graph of Entities

18. A Graph of Services

19. http://www.bestbuy.com/site/She+Wolf…
http://www.daylife.com/topic/Shakira
http://twitter.com/shakira
http://www.facebook.com/shakira
http://www.myspace.com/shakira
http://www.last.fm/music/Shakira
http://www.netflix.com/RoleDisplay/Shakira/20046629
http://www.guardian.co.uk/music/shakira

20. eMQL: MQL Extensions
• Request data from other service providers
• Services accessed transparently within MQL query
• Use Freebase Keys/Properties in external service request
• Uses:
• real-time data services
• Stock quotes, sensor data
• premium services
• requests can specify private "api keys" for the service
• fine grained & authoritative data sources

21. eMQL Query
{
"id": "/en/ibm",
ticker
"type": "/business/company",
"ticker_symbol": [{
"ibm"
"stock_exchange": null,
"ticker_symbol":null
}]
}

22. eMQL Query
{
"id": "/en/ibm",
"type": "/business/company", ticker
"ticker_symbol": [{
"stock_exchange": null, "ibm"
"ticker_symbol":null,
"quote":null
}]
}

23. eMQL Query
{
"id": "/en/ibm",
"type": "/business/company", ticker
"ticker_symbol": [{
"stock_exchange": null, "ibm"
"ticker_symbol":null,
"quote":null "pre"
}]
}
"fetch"

24. eMQL Service Request
• Pre
• Modify MQL query to provide additional information
necessary to complete request
• e.g., retrieve specific namespace keys
• Fetch
• Produce (retrieve, calculate, format) value for the
eMQL property
• Reduce (optional)
• Create a result that looks across all results returned
in the query
• Help
• Document how the property is used

25. MQL Read Service
http://api.freebase.com/api/service/mqlread?query=
{"query":{"id":"/en/ncis", "name":null}}
http://api.freebase.com/api/service/mqlread?queries=
{"q0":{"query":{"id":"/en/ncis", "name":null}}}
{"q1":{"query":{"id":"/en/blade_runner", "name":null}}}

26. MQL Requests in PHP
{"id":"/en/ncis", "name":null}
$topicid = "/en/ncis";
$simplequery = array('id'=>$topicid, 'name'=>null);
$queryarray = array('q1'=>array('query'=>$simplequery)); #query envelope
$jsonquerystr = json_encode($queryarray);
$mqlurl =
"http://www.freebase.com/api/service/mqlread?queries=". $jsonquerystr;
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $mqlurl);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$resultstr = curl_exec($ch);
curl_close($ch);
$resultarray = json_decode($resultstr, true); #true:give us an array
$topicname = $resultarray["q1"]["result"]["name"]

27. Demo eMQL Extensions
stock quote
@tag references

28. TV Episode Adapter
Query:
{
"id":"/en/ncis",
"/user/jamie/extension/tv_episode": null
}
Desired
Data: "name":"Faith"
"airdate": "Dec/15/2009"
"id":"/authority/tvrage/episode/1064868143"

29. TV Rage Episode Adapter

30. http://services.tvrage.com/tools/quickinfo.php?show=NCIS
Show ID@4628
Show Name@NCIS
Show URL@http://www.tvrage.com/NCIS
Premiered@2003
Started@Sep/23/2003
Ended@
Latest Episode@07x09^Child's Play^Nov/24/2009
Next Episode@07x10^Faith^Dec/15/2009
RFC3339@2009-12-15T20:00:00-5:00
GMT+0 NODST@1260921600
Country@USA
Status@Returning Series
Classification@Scripted
Genres@Action | Crime | Drama | Military/War
Network@CBS
Airtime@Tuesday at 08:00 pm
Runtime@60

31. TV Episode Adapter
eMQL Driver
TV Rage
Time
query dispatched
pre
eMQL
MQL Query
Extend MQL query to retrieve
TV Rage Key (program identifier)
updated MQL
query
Adapter
TV Rage Service
run MQL
query
MQL
results Life Cycle
fetch
get series
data
next episode
number,
name,date
get episode
data
next
episode
URL
format results
results
return
query
results

32. Using Foreign Identifiers
to locate Freebase Topics
• /authority Namespace
• Organizations managing stable entity identifiers
• /source - identifiers only appearing in URLs
• Keys can be for URLs to other sites
• And vice-versa!

33. URLs and Freebase Keys
• http://www.imdb.com/title/tt0083658
• /authority/imdb/title/tt0083658
• http://www.rottentomatoes.com/alias?type=imdbid&s=0083658
• http://dbpedia.org/resource/Blade_Runner
• /wikipedia/en/Blade_Runner
• http://en.wikipedia.org/wiki/Blade_Runner
• http://musicbrainz.org/artist/2c4dae8c-
e591-49e0-9c5a-62b310a15788.html
• /authority/musicbrainz/2c4dae8c-
e591-49e0-9c5a-62b310a15788
• http://www.bbc.co.uk/music/artists/2c4dae8c-
e591-49e0-9c5a-62b310a15788

34. http://ids.freebaseapps.com

35. Using Freebase RDF URIs
http://rdf.freebase.com/ns/<freebase-key>
• Performs content negotiation (HTTP ACCEPT Header)
• Produces HTML for standard browsers
• Produces RDF if you ask for it
• Easily translated to MQL style Freebase identifiers
http://rdf.freebase.com/ns/en.ncis = /en/ncis

36. Entity Extractors
• Zemanta
• Freebase RDF URIs
• Wikipedia Links
• IMDB identifiers
• Orchestr8
• Freebase RDF URIs
• DBPedia RDF URIs
• MusicBrainz identifiers
• Crunchbase identifiers
• OpenCalais
• Freebase RDF URIs
• DBPedia RDF URIs

37. Getting Started++
• Freebase Documentation Hub
• http://www.freebase.com/docs
• Developer Mailing List
• http://freebase.markmail.org/search/?q=list:com.freebase.developers
• Schema/Modeling assistance
• Data Modeling Mailing List
• http://freebase.markmail.org/search/?q=list:com.freebase.data-modeling
• Real Time help on IRC
• Freenode #freebase
• Freebase Happenings
• http://blog.freebase.com