sql - Ruby on Rails: joining two tables on something other than the standard foreign key -

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मेरे पास एक रेल क्वेरी है जैसे: 

  @user = User.find_by_username (params [ : खोज],: शामिल = & gt; [: user_similars])

मॉडल: उपयोगकर्ता (has_many: user_similars), user_similar (is_to: उपयोगकर्ता)

उपयोगकर्ता_सिमिलर mysql तालिका में एक "user_id" फ़ील्ड एक विदेशी कुंजी के रूप में है, लेकिन मुझे नहीं चाहिए: इस उदाहरण के लिए इसमें शामिल होने के लिए शामिल करें मैं "user_id_similar" नामक एक अन्य क्षेत्र में शामिल होना चाहता हूं

क्या कोई तरीका बदलना है: इसमें शामिल होना चाहिए ताकि वह किसी अन्य क्षेत्र में शामिल हो सके?

क्या मुझे होना चाहिए का उपयोग कर: एक अलग विकल्प के साथ जुड़ें?

या शायद मॉडल पद्धति घोषणाएं संपादित करें?

धन्यवाद!

जब आप दो तालिकाओं के बीच के संबंध को परिभाषित करते हैं, तो आप निर्दिष्ट करें कि किस कॉलम को विदेशी कुंजी के रूप में उपयोग करना है इस मामले में, "user_id_similar" को एफके बनने के लिए सेट करें, और इसमें तब शामिल होना चाहिए जब सम्मिलित हों


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