sql server 2005 - SQL: how to select single record for multiple id's on the basis of max datetime? -

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मेरे पास निम्न एसक्यूएल तालिका है, 

  आईडी विंड स्पीड तिथि टाइम ------ -------------------------------- 1 1.1 2009-09-14 16: 11: 38.383 1 1.9 2009-09- 15 16: 11: 38.383 1 2.0 2009-09-16 16: 11: 38.383 1 1.8 2009-09-17 16: 11: 38.383 1 1.7 2009-09-19 16: 11: 38.382 2 1. 9 2009-09-19 16 : 11: 38.383 1 1.6 2009-09-19 16: 11: 38.383 2 1.2 2009-09-20 16: 11: 38.383

मैं एक प्रश्न लिखना चाहता हूं जो मुझे वापस लौटा देगा उपरोक्त तालिका से निम्नलिखित परिणाम सेट करें: 

  आईडी विंड स्पीड तिथि टाइम ----------------------------- --------- 1 1.6 2009-09-19 16: 11: 38.383 2 1.2 2009-09-20 16: 11: 38.383

उपर्युक्त reuslt में नवीनतम (उस आईडी के लिए नवीनतम दिनांक समय के आधार पर) एकल प्रविष्टि। जिसका अर्थ है कि मेरे पास कई रिकॉर्ड आईडी है जो डेटटाइम के साथ है

मैं सभी आईडी के नवीनतम एकल प्रविष्टि प्राप्त करना चाहता हूं। 

  SELECT a.Id, a.WindSpeed, a.DateTime से एक INNER JOIN के रूप में (SELECT ID, मैक्स (दिनांकटाइम) एडी तिथि के समय से आपकेटेबल ग्रुप आईडी पर) as.ID = b.ID और a.DateTime = बी.डेटटाइम

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