class ActiveRecord::Relation::ExplainProxy

def average(column_name)
  exec_explain { @relation.average(column_name) }
end

def count(column_name = nil)
  exec_explain { @relation.count(column_name) }
end

def exec_explain(&block)
  @relation.exec_explain(@relation.collecting_queries_for_explain { block.call }, @options)
end

def first(limit = nil)
  exec_explain { @relation.first(limit) }
end

def initialize(relation, options)
  @relation = relation
  @options  = options
end

def inspect
  exec_explain { @relation.send(:exec_queries) }
end

def last(limit = nil)
  exec_explain { @relation.last(limit) }
end

def maximum(column_name)
  exec_explain { @relation.maximum(column_name) }
end

def minimum(column_name)
  exec_explain { @relation.minimum(column_name) }
end

def pluck(*column_names)
  exec_explain { @relation.pluck(*column_names) }
end

def sum(identity_or_column = nil)
  exec_explain { @relation.sum(identity_or_column) }
end