sql - I want to do INSERT without record in DB -

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उपरोक्त प्रश्न का गैर-मूल अंग्रेजी से अंग्रेज़ी का अनुवाद:

यह एक प्रश्न है डेटाबेस में मान डालने का उपयोग करने के लिए सबसे तेज़ तरीका, जब मान पहले से डेटाबेस में हो सकता है INSERT असफल हो जायेगा जब मूल्य होता है और अद्यतन नहीं होगा जब यह नहीं है। इनमें से कौन सा विकल्प सबसे अधिक वांछनीय है?

  • पहले चुनें और INSERT या अद्यतन चुनें।
  • पहले डालें और अद्यतन करें यदि इसकी एक डुप्लिकेट त्रुटि है।

    • यदि उपर्युक्त के अलावा अन्य अच्छे विकल्प हैं, तो कृपया मुझे सिखाएं।

    पर्यावरण MySQL 4.1 का उपयोग करता है।

यदि आप ऐसा एक बयान में करना चाहते हैं (लगता है कि आप क्या चाहते हैं), मैं INSERT ... पर डुप्लिकेट कुंजी अद्यतन का उपयोग करने की सिफारिश करेगा सिंटेक्स, निम्न प्रकार से: 

  सारणी (IN, someothervalue) मूल्यों में INSERT (1, 'हाय माँ') डुप्लिकेट की कुंजी अद्यतन someothervalue = 'hi mom';

निर्दिष्ट कुंजी मान (या तो प्राथमिक कुंजी या अद्वितीय) के साथ कोई मौजूदा रिकॉर्ड नहीं है तो प्रारंभिक INSERT कथन निष्पादित होगा। यदि कोई रिकॉर्ड पहले से मौजूद है, तो निम्न UPDATE स्टेटमेंट ( someothervalue = 3 ) निष्पादित किया जाता है।

यह MySQL के सभी संस्करणों में समर्थित है अधिक जानकारी के लिए,

देखें

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