class ConceptQL::Operators::Sum

Public Instance Methods

query(db) click to toggle source
# File lib/conceptql/operators/sum.rb, line 17
def query(db)
  db.from(unioned(db))
    .select_group(*(dynamic_columns - [:start_date, :end_date, :criterion_id, :value_as_number]))
    .select_append(Sequel.lit('?', 0).as(:criterion_id))
    .select_append{ min(start_date).as(:start_date) }
    .select_append{ max(end_date).as(:end_date) }
    .select_append{sum(value_as_number).as(:value_as_number)}
    .from_self
end
unioned(db) click to toggle source
# File lib/conceptql/operators/sum.rb, line 27
def unioned(db)
  upstreams.map { |c| c.evaluate(db) }.inject do |uni, q|
    uni.union(q)
  end
end