Question: When did San Francisco (the one whose population is 827420 serve as the narrative location for  Doctor Who (the one that origins from Canada)?
Choices: 1999
2014
1957-01-01
2009-11-20
1998-07-15
1903-01-01
2004-07-07
2008-04-23
1810
1800-01-01
SPARQL: SELECT DISTINCT ?qpv WHERE { ?e_1 <pred:name> "Doctor Who" . ?e_1 <country_of_origin> ?e_3 . ?e_3 <pred:name> "Canada" . ?e_2 <pred:name> "San Francisco" . ?e_2 <population> ?pv . ?pv <pred:unit> "1" . ?pv <pred:value> "827420"^^xsd:double . ?e_1 <narrative_location> ?e_2 . [ <pred:fact_h> ?e_1 ; <pred:fact_r> <narrative_location> ; <pred:fact_t> ?e_2 ] <point_in_time> ?qpv .  }
Program:
function: Find
inputs: Canada
function: Relate
dependencies: 0
inputs: country of origin
backward
function: Find
inputs: Doctor Who
function: And
dependencies: 1
2
function: Find
inputs: San Francisco
function: FilterNum
dependencies: 4
inputs: population
827420
=
function: QueryRelationQualifier
dependencies: 3
5
inputs: narrative location
point in time
Answer: 1999