sum(column_name, options = {})
Calculates the sum of values on a given column. The value is returned with the same data type of the column, 0 if there’s no row. See calculate for examples with options.
Person.sum('age') # => 4562
# File activerecord/lib/active_record/relation/calculations.rb, line 92 def sum(column_name, options = {}) calculate(:sum, column_name, options) end
