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validates_uniqueness_of fails when primary key value changed

#5117

class Role
  set_primary_key :short_name
  validates_uniqueness_of :name
end

test "validates_uniqueness_of" do
  r = Role.new(:name => "name" )
  r.short_name = "first"
  r.save!

  r.short_name = "second"
  assert r.valid?
  assert_equal 0, r.errors[:name].size
end

The validation fails when it should not.
The query that is generated by uniqueness validation is:
SELECT "roles"."short_name" FROM "roles" WHERE ("roles"."name" = 'name') AND ("roles".short_name <> 'second') LIMIT 1
The query uses the changed, unsaved short_name (primary_key) value which is "second" instead of the previous one ("first") when checking on db for other records that could have the same :name.

This is not nice when someone wants to use natural keys as primary keys.

Reported by Robert Pankowecki · July 15th, 2010 @ 10:27 AM

Activity

Subba

even when primary key is natural if you set change the id rails is not resetting
see below example.

class Car < ActiveRecord::Base
  validates_uniqueness_of :name
end


ruby-1.8.7-p174 > c = Car.create(:name => "Nissan")
  Car Load (0.4ms)  SELECT "cars"."id" FROM "cars" WHERE ("cars"."name" = 'Nissan') LIMIT 1
  SQL (0.3ms)  INSERT INTO "cars" ("name") VALUES ('Nissan')
 => #<Car id: 2, name: "Nissan"> 
ruby-1.8.7-p174 > c.id = 3
 => 3 
ruby-1.8.7-p174 > c.valid?
  Car Load (0.5ms)  SELECT "cars"."id" FROM "cars" WHERE ("cars"."name" = 'Nissan') AND ("cars".id <> 3) LIMIT 1
 => false

July 16th, 2010 @ 09:49 PM

Santiago Pastorino
- State changed from new to open
This issue has been automatically marked as stale because it has not been commented on for at least three months.

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February 2nd, 2011 @ 04:35 PM
Santiago Pastorino
- State changed from open to stale
February 2nd, 2011 @ 04:35 PM