How to order, group, order with mySQL -

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यह मेरी तालिका का सरलीकृत संस्करण है 

  tbl_records -title -created-views < / Code>

मैं सोच रहा हूं कि मैं एक क्वेरी कैसे कर सकता हूं जहां उन्हें शीर्षक से समूहीकृत किया जाता है, लेकिन प्रत्येक समूह के लिए दिया गया रिकॉर्ड सबसे हाल ही में बनाया गया है मैं फिर इसे विचारों के लिए आदेश देगा।

मुझे लगता है कि एक तरह से एक उप क्वेरी करने के लिए और इसे बनाया द्वारा क्रम और फिर शीर्षक द्वारा समूह है और फिर उन परिणामों से दृश्यों के द्वारा आदेश मुझे लगता है कि हालांकि एक बेहतर तरीका है।

धन्यवाद

संपादित करें:

नमूना डेटा:

<पूर्व> - शीर्षक: ग्नू डिज़ाइन -उपचार किया गया: 2009-11-11 14:47:18 -यहां: 104 -चिह्नः ग्नू डिज़ाइन किया गया: 2010-01-01 21:37:09 -उप दृश्य: 9- शीर्षक: फ़्रेंच कनेक्शन -सैटेड: 2010-05-01 09:27:19 -views: 20

मुझे परिणाम होना चाहिए:

< पूर्व> - शीर्षक: फ्रांसीसी कनेक्शन -सैटेड: 2010-05-01 09:27:19 -प्रदर्शन: 20- शीर्षक: ग्नू डिज़ाइन -उत्पादित: 2010-01-01 21:37:09 -दृश्य: 9 < / कोड>

केवल सबसे हालिया ग्नू डिज़ाइन दिखाया गया है और फिर परिणामों के विचारों के अनुसार क्रमबद्ध हैं।

यह सबसे बड़ी एन-प्रति-समूह समस्या का एक उदाहरण है जो स्टैक ओवरफ्लो पर अक्सर दिखाई देता है।

यह मेरा सामान्य समाधान है:

< प्री> SELECT T1। * Tbl_records T1 बाएं OUTER से tbl_records t2 ON (t1.title = t2.title और (t1.created & lt; t2.created या t1.created = t2.created और t1.primar Ykey & lt; T2.primarykey)) WHERE t2.title NULL है;

स्पष्टीकरण: पंक्ति t1 को खोजने के लिए जिसके लिए कोई अन्य पंक्ति t2 उसी कोड के साथ मौजूद नहीं है और एक बड़ा बनाया दिनांक संबंधों के मामले में टाई को हल करने के लिए कुछ अनोखी कुंजी का उपयोग करें, जब तक कि title ।


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