sql - In MySQL, how can I find the sum of the N largest values grouped on a particular column? -


संभव डुप्लिकेट:

मेरे पास निम्न डेटा है। 

  id val smith 20 smith 10 smith 8 smith 30 jones 40 jones 10 jones 30 jones 30   
 मुझे तब क्या चाहिए आईडी द्वारा समूह के लिए है और प्रत्येक आईडी के लिए दो सबसे बड़े मानों को जोड़ता है।  
  30 से 30 + 20 जोन्स 70 से 40 + 30   
 धन्यवाद   
 
 
 यदि आप प्रत्येक ID के लिए केवल शीर्ष दो मानों की राशि प्राप्त करने के बारे में चिंतित नहीं थे तो आप यह चाहते हैं:  
  SELECT SUM (val) से तालिका_नाम समूह आईडी आईडी द्वारा आईडी एएससी   
 हालांकि, "मैं शीर्ष एन कैसे प्राप्त करूं समूह के भीतर मूल्य "प्रश्न एक डुप्लिकेट है, यहां उत्तर दिया गया:

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