database - Efficiently sorting data from DB using Java? -


हमारे पास क्या है:

3 MySQL डीबी टेबल: उपयोगकर्ता, टेक्स्ट, मित्र

< उपयोगकर्ता : उपयोगकर्ता नाम, पासवर्ड, ईमेल, आदि।

पाठ : उपयोगकर्ता नाम, पाठ, तिथि आदि।

दोस्त : उपयोगकर्ता नाम, मित्र, उपयोगकर्ता नाम, आदि।

कार्य:

अपने मित्रों से 10 नवीनतम ग्रंथों को दिखाने के लिए एल्गोरिदम (जावा में) लिखें <

डीबी तालिकाओं को संशोधित किया जा सकता है (नया जोड़ दिया गया है)।

डेटा मात्रा: 200 000 उपयोगकर्ता, ~ 50 पाठ प्रति उपयोगकर्ता।

मैं किसी भी विचार, उदाहरण, अंक, आदि की सराहना करता हूँ। धन्यवाद आप!

(होमवर्क नहीं। शुद्ध समस्या, प्रदर्शन सुधार की तलाश में)

आपने यह नहीं कहा था कि कौन सा डेटाबेस है, इसलिए मैं सिर्फ एक धारणा (नीचे पोस्टग्रेस वाक्यविन्यास) करूँगा: 

  चुनें। एफ पर f.frie Nd_username = t.username जहां f.username = 'myusername' का आदेश t.date द्वारा वर्णित है LIMIT 10

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