PG操作員不存在：uuid =文本

Question

我有模型Conversation，User，它們通過has_many *, through: users_conversations連接。

我有這樣的範圍：

class Conversation < ActiveRecord::Base 
    has_many :users_conversations 
    has_many :users, through: :users_conversations 

    scope :by_participants, ->(ids) { 
    joins(:users).where("users.id = ALL (ARRAY[?])", ids) 
    } 
end 

預計找談話，在所有需要用戶的參與（嚴格）。

Conversation.by_participants first 
    Failure/Error: its(:first) {is_expected.to eq(@conversation)} 

    ActiveRecord::StatementInvalid: 
     PG::UndefinedFunction: ERROR: operator does not exist: uuid = text 
     LINE 1: ...= "users_conversations"."user_id" WHERE (users.id = ALL (ARR... 
                    ^
     HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. 
     : SELECT "conversations".* FROM "conversations" INNER JOIN "users_conversations" ON "users_conversations"."conversation_id" = "conversations"."id" INNER JOIN "users" ON "users"."id" = "users_conversations"."user_id" WHERE (users.id = ALL (ARRAY['7c1a06c8-10c7-417f-96ea-c9c50fcaed35','8af2beca-d5f2-48d7-9857-7b5d124eaac1'])) ORDER BY "conversations"."id" ASC LIMIT 1 
    # ./spec/models/conversation_spec.rb:19:in `block (3 levels) in <top (required)>' 

我試圖注入陣列cast (*) as uuid，但PG似乎認爲這是隻是字符串：

HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. 
     : SELECT "conversations".* FROM "conversations" INNER JOIN "users_conversations" ON "users_conversations"."conversation_id" = "conversations"."id" INNER JOIN "users" ON "users"."id" = "users_conversations"."user_id" WHERE (users.id = ALL (ARRAY['cast (6d4ff0b3-e148-40f8-87b5-d4d03577577a as uuid)','cast (432f4f6e-5832-4831-80dc-c747b8d3e742 as uuid)'])) 

Answer 1

你有沒有試過這種

class Conversation < ActiveRecord::Base 
    has_many :users_conversations 
    has_many :users, through: :users_conversations 

    scope :by_participants, ->(ids) { 
    joins(:users).where("users.id = ALL (ARRAY[?]::uuid[])", ids) 
    # it's all about ARRAY[?]::uuid[] type cast 
    } 
end 

你的目標列::uuid[]但來源是text，只需鍵入cast並查看結果。