StackOverflow's Popularity algorithm in MySQL -

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आप MySQL में SO की लोकप्रियता एल्गोरिथ्म कैसे लिखेंगे?

धन्यवाद!

< पी> यह अपेक्षाकृत सरल है

<पूर्व> t = (प्रविष्टि पोस्ट का समय) - (8 दिसंबर, 2005)

आप दिनांक मानों को टाइमस्टैम्प में परिवर्तित कर सकते हैं (आप उपयोग कर सकते हैं), जो आपको एक पूर्णांक देता है जिसका इस्तेमाल बाकी हिस्सों में किया जा सकता है। 

  x = upvotes - downvotes

यह एक बहुत आसान होना चाहिए .. जाहिर है, MySQL घटाव का समर्थन करता है। 

  y = {1 यदि x & gt; 0, 0 यदि x = 0, -1 यदि x & lt; 0) z = {1 अगर x & lt; 0, अन्यथा x}

इन के लिए, MySQL के बयान पर एक नज़र डालें। 

  लॉग (z) + (y * t) / 45000   
 माईएसक्यूएल एक फ़ंक्शन है, इसलिए यह एक आसान होना चाहिए, बस सरल गणित।  
 और, आप एक बयान के साथ सब एक साथ टाई। आप अपने  चयन करें  कथन में मध्यवर्ती गणनाओं का उपयोग करके का उपयोग कर सकते हैं। उदाहरण के लिए:  
  का चयन करें @ x: = (upvotes - downvotes) x के रूप में, (xx & gt; 4) asXGreaterThanFour

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