DocumentDB SQL – 按子句排序

Microsoft Azure DocumentDB 支持使用 SQL over JSON 文档查询文档。您可以在查询中使用 ORDER BY 子句根据数字和字符串对集合中的文档进行排序。该子句可以包含一个可选的 ASC/DESC 参数来指定必须检索结果的顺序。

我们将考虑与前面示例中相同的文档。

以下是AndersenFamily文档。

{ 
   "id": "AndersenFamily", 
   "lastName": "Andersen", 
	
   "parents": [ 
      { "firstName": "Thomas", "relationship":  "father" }, 
      { "firstName": "Mary Kay", "relationship":  "mother" } 
   ],
   
   "children": [ 
      { 
         "firstName": "Henriette Thaulow", 
         "gender": "female", 
         "grade": 5, 
         "pets": [ { "givenName": "Fluffy", "type":  "Rabbit" } ] 
      } 
   ],
   
   "location": { "state": "WA", "county": "King", "city": "Seattle" }, 
   "isRegistered": true 
}

以下是SmithFamily文档。

{ 
   "id": "SmithFamily", 
	
   "parents": [ 
      { "familyName": "Smith", "givenName": "James" }, 
      { "familyName": "Curtis", "givenName": "Helen" } 
   ],
   
   "children": [ 
      {
         "givenName": "Michelle", 
         "gender": "female", 
         "grade": 1 
      },
		
      { 
         "givenName": "John", 
         "gender": "male", 
         "grade": 7,
			
         "pets": [ 
            { "givenName": "Tweetie", "type": "Bird" } 
         ] 
      } 
   ],
   
   "location": { 
      "state": "NY", 
      "county": "Queens", 
      "city": "Forest Hills" 
   },
   
   "isRegistered": true 
} 

以下是WakefieldFamily文档。

{ 
   "id": "WakefieldFamily", 
	
   "parents": [ 
      { "familyName": "Wakefield", "givenName": "Robin" }, 
      { "familyName": "Miller", "givenName": "Ben" } 
   ],
   
   "children": [ 
      { 
         "familyName": "Merriam", 
         "givenName": "Jesse", 
         "gender": "female", 
         "grade": 6,
			
         "pets": [ 
            { "givenName": "Charlie Brown", "type": "Dog" },
            { "givenName": "Tiger", "type": "Cat" }, 
            { "givenName": "Princess", "type": "Cat" } 
         ] 
      },
		
      { 
         "familyName": "Miller", 
         "givenName": "Lisa", 
         "gender": "female", 
         "grade": 3,
			
         "pets": [ 
            { "givenName": "Jake", "type": "Snake" } 
         ] 
      } 
   ],
   
   "location": { "state": "NY", "county": "Manhattan", "city": "NY" }, 
   "isRegistered": false 
} 

我们来看一个简单的例子。

以下是包含 ORDER BY 关键字的查询。

SELECT  f.id, f.children[0].givenName,f.children[0].grade  
FROM Families f  
ORDER BY f.children[0].grade

执行上述查询时，会产生以下输出。

[ 
   { 
      "id": "SmithFamily", 
      "givenName": "Michelle", 
      "grade": 1 
   },
	
   { 
      "id": "AndersenFamily", 
      "grade": 5 
   },
	
   { 
      "id": "WakefieldFamily", 
      "givenName": "Jesse", 
      "grade": 6 
   } 
] 

让我们考虑另一个简单的例子。

以下是包含 ORDER BY 关键字和 DESC 可选关键字的查询。

SELECT f.id, f.parents[0].familyName 
FROM Families f  
ORDER BY f.parents[0].familyName DESC

执行上述查询时，将产生以下输出。

[ 
   {
      "id": "WakefieldFamily", 
      "familyName": "Wakefield" 
   },
	
   { 
      "id": "SmithFamily", 
      "familyName": "Smith" 
   },
	
   {
      "id": "AndersenFamily" 
   }
]