************************************************
# List everything in db
SELECT ?subject ?predicate ?object
WHERE {
  ?subject ?predicate ?object
}
LIMIT 25


***********************************************
# List all tages
PREFIX ga: <http://games.com/ns/#> 

SELECT  ?game
WHERE {
    ?game ga:tag ga:strategy
}


**********************************************
# Games that Torstein likes
PREFIX fb: <http://facebook.com/ns/#> 
PREFIX ga: <http://games.com/ns/#> 
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 

SELECT  ?title
WHERE {
    fb:torstein fb:like ?game . 
}


**********************************************
# Select game title for games with same 
# tag as other games Torstein likes
PREFIX fb: <http://facebook.com/ns/#> 
PREFIX ga: <http://games.com/ns/#> 
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 

SELECT  ?game2
WHERE {
    ?game1 ga:tag ?t . 
    ?game2 ga:tag ?t .
    FILTER ( ?game1 != ?game2) .
    fb:torstein fb:like ?game1 . 
}


**********************************************
# List all sub-classes
PREFIX fb: <http://facebook.com/ns/#> 
PREFIX ga: <http://games.com/ns/#> 
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 

SELECT  ?subcl
WHERE {
    ?subcl rdfs:subClassOf ?c
}