我正在使用hstore进行项目,我有一个迁移文件:
class CreateShippingCategories < ActiveRecord::Migration
def change
create_table :shipping_categories do |t|
t.string :name
t.hstore :size
t.integer :price_transport
t.integer :price_storage
t.timestamps
end
end
end
默认情况下,我有4种类别,我决定在seeds.rb文件中创建它们,如下所示:
shipping_categories = [
[ "Small", {L: 40, B: 30, H: 22}, 700, 100],
[ "Medium", {L: 60, B: 40, H: 32}, 900, 400],
[ "Large", {L: 60, B: 52, H: 140}],
[ "XX Large", {L: 200, B: 50, H: 200}]
]
shipping_categories.each do |name, size, price_transport, price_storage|
ShippingCategory.where(name: name, size: size, price_transport: price_transport, price_storage: price_storage).first_or_create
end
但是当我尝试运行rake db:seed时出现此错误:
rake aborted!
ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR: missing FROM-clause entry for table "size"
LINE 1: ... WHERE "shipping_categories"."name" = 'Small' AND "size"."L"...
^
: SELECT "shipping_categories".* FROM "shipping_categories" WHERE "shipping_categories"."name" = 'Small' AND "size"."L" = 40 AND "shipping_categories"."price_transport" = 700 AND "shipping_categories"."price_storage" = 100 ORDER BY "shipping_categories"."id" ASC LIMIT 1
有没有人有任何想法如何解决这个问题?
答案 0 :(得分:3)
问题在于您在find
的{{1}}部分中查询的方式。我怀疑你要做的只是创建find_or_create
,如果它不存在的话。这个名字是独特的吗?如果是这样,你可以这样做:
ShippingCategory
有关详细信息,请参阅find_or_create_by的文档。