DocumentDB - 記錄排序

Microsoft Azure DocumentDB 語言 SQL 支援對 JSON 文件執行查詢。您可使用查詢中的 ORDER BY 子句對集合中的文件根據數字和字串進行排序。該子句可包括可選的 ASC/DESC 引數以指定檢索結果的順序。

我們來看看以下有 JSON 文件的示例。

{ 
   "id": "Food Menu",
   "description": "Grapes, red or green (European type, such as Thompson seedless), raw",
	
   "tags": [
      {
         "name": "grapes"
      },
		
      {
         "name": "red or green (european type"
      },
		
      {
         "name": "such as thompson seedless)"
      },
		
      {
         "name": "raw"
      }
   ],
	
   "foodGroup": "Fruits and Fruit Juices",
	
   "servings": [
      {
         "amount": 1,
         "description": "cup",
         "weightInGrams": 151
      },
		
      {
         "amount": 10,
         "description": "grapes",
         "weightInGrams": 49
      },
		
      {
         "amount": 1,
         "description": "NLEA serving",
         "weightInGrams": 126
      }
   ]
	
}

以下是按降序對結果進行排序的 SQL 查詢。

SELECT f.description, f.foodGroup,  
   f.servings[2].description AS servingDescription,  
   f.servings[2].weightInGrams AS servingWeight  
	
FROM f  
ORDER BY f.servings[2].weightInGrams DESC 

執行上述查詢時，您將收到以下結果。

[
   {
      "description": "Grapes, red or green (European type, such as Thompson
         seedless), raw",
      "foodGroup": "Fruits and Fruit Juices",
      "servingDescription": "NLEA serving",
      "servingWeight": 126
   }
]