Question

當我試圖通過指定藝術家讓所有的音頻歌曲中獲取數據的時候，我得到錯誤：

ActiveRecord::StatementInvalid: PGError: ERROR: column reference "artist" is ambiguous 
LINE 1: ... AND (audio_translations.artist IS NOT NULL) AND (artist = '... 
                  ^
: SELECT "audios"."id" AS t0_r0, "audios"."audio_genre_id" AS t0_r1, "audios"."song" AS t0_r2, "audios"."artist" AS t0_r3, "audios"."file_id" AS t0_r4, "audios"."photo_id" AS t0_r5, "audios"."description" AS t0_r6, "audios"."position" AS t0_r7, "audios"."created_at" AS t0_r8, "audios"."updated_at" AS t0_r9, "audios"."date" AS t0_r10, "audio_translations"."id" AS t1_r0, "audio_translations"."audio_id" AS t1_r1, "audio_translations"."locale" AS t1_r2, "audio_translations"."artist" AS t1_r3, "audio_translations"."song" AS t1_r4, "audio_translations"."description" AS t1_r5, "audio_translations"."created_at" AS t1_r6, "audio_translations"."updated_at" AS t1_r7 FROM "audios" LEFT OUTER JOIN "audio_translations" ON "audio_translations"."audio_id" = "audios"."id" WHERE "audio_translations"."locale" = 'en' AND (audio_translations.artist IS NOT NULL) AND (artist = 'Andy') 

我用下面的語句AR：

Audio.with_translations(I18n.locale).find(:all, :conditions => ["artist = ?", 'Andy']) 

它工作沒有with_translations方法：

>> Audio.find(:all, :conditions => ["artist = ?", 'Andy']) 
=> [#<Audio id: 10, audio_genre_id: 1, song: "My heart, my life", artist: "Andy", file_id: 1, photo_id: nil, description: "...", position: 2, created_at: "2011-07-12 07:24:43", updated_at: "2011-07-12 08:31:21", date: "2011-07-12 07:24:00">] 

Answer 1

嘗試改變

Audio.with_translations(I18n.locale).find(:all, :conditions => 
    ["artist = ?", 'Andy']) 

到

Audio.with_translations(I18n.locale).find(:all, :conditions => 
    ["audios.artist = ? OR audio_translations.artist ?", 'Andy', 'Andy']) 

此查詢不SQL連接具有相同的列兩個表的

Answer 2

ActiveRecord的StatementInvalid是模糊的是說的敷設方式：先生，你的SQL語句不是有道理的，因爲你正在檢查的領域是在幾張桌子上找到的，我不知道用哪一種。

嘗試在任何地方指定表名，例如audios.artist和audio_translations.artist。