anchor.diff:  ----
   
   Union Queries
  -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  +~~~~~~~~~~~~~
   
   .Select all persons who have developed a software in java using union.
  +
   [source,SPARQL]
   ----
   SELECT * WHERE {
  
positive.code: 
  
   Optional Queries
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  coming soon
  
  
  
  Query modifier - Order By
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  .Select all vertices with the label `person` and order them by their age.
  [source,SPARQL]
  ----
  SELECT * WHERE {
  
negative.code: ----
  
  Query modifier - Group By
  ~~~~~~~~~~~~~~~~~~~~~~~~~
  
  .Select all vertices with the label `person` and group them by their age.
  [source,SPARQL]
  ----
  SELECT * WHERE {
    ?person v:label "person" .
  