Displaying 2 results from an estimated 2 matches for "tax_rat".
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tax_rate
2006 Aug 13
4
has_many and foreign_key question
...veRecord::Migration
def self.up
create_table :properties do |t|
t.column :address, :string
t.column :jurisdiction_id, :string
end
end
class CreateJurisdictionRates
def self.up
create_table :jurisdiction_rates do |t|
t.column :jurisdiction_id, :string
t.column :tax_rate, :string
t.column :type, :string
end
end
Rails of course sets up auto incrementing ''id'' columns on both tables.
Now there are many properties in the same tax jurisdiction that will
have the same rates applied to them, so all properties in
''jurisidiction_id'...
2006 Jul 02
0
Rails Core Weekly June 19 - July 2 2006
...dy it
nevertheless to sharpen your Ruby-mind.
Also, DHH adds Enumerable#sum for calculating a sum from the elements
(incidently shadowing AssociationCollection#sum but that is fixed
quickly enough). Also Jeremy makes it a bit better by making it
block-less Example:
payments.sum { |p| p.price * p.tax_rate }
payments.sum(&:price)
or simply block-less:
[1,2,3].sum # => 6
DHH explains this is instead of
payments.inject(0) { |sum, p| sum + p.price }
In fact the implementation of #sum is virtually the same:
inject(0) { |sum, element| sum + yield(element) }
Quickly thereafter Nick Seckar ad...