django - Get last record in a queryset -


मैं एक निश्चित ख़तरनाक में अंतिम रिकॉर्ड कैसे प्राप्त करूं?

आप बस ऐसा कुछ कर सकते हैं, इसका उपयोग कर: 

  queryset.reverse () [0]

इसके अलावा, Django दस्तावेज़ीकरण से यह चेतावनी सावधान रहें:

... ध्यान दें कि रिवर्स () को आम तौर पर केवल एक QuerySet पर कॉल किया जाना चाहिए, जिसमें एक परिभाषित क्रम (उदाहरण के लिए, जब कोई मॉडल जो कि एक डिफ़ॉल्ट ऑर्डर देने को परिभाषित करता है, या order_by () ) का उपयोग करते समय क्वेरी करता है। यदि कोई ऐसा आदेश किसी दिए गए QuerySet के लिए निर्धारित नहीं है, तो रिवर्स () पर कोई वास्तविक प्रभाव नहीं होता है (आदेश reverse () कॉल करने से पहले अपरिभाषित था < / कोड>, और बाद में अपरिभाषित रहेगा)।


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