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📜  DocumentDB SQL-关键字之间

📅  最后修改于: 2020-11-28 13:34:29             🧑  作者: Mango

关键字BETWEEN用于表示对值范围的查询，例如SQL。 BETWEEN可用于字符串或数字。在DocumentDB和ANSI SQL中使用BETWEEN的主要区别在于，您可以针对混合类型的属性表达范围查询。

例如，在某些文档中，可能有“等级”作为数字，而在其他文档中，则有可能是字符串。在这些情况下，两种不同类型的结果之间的比较是“未定义的”，并且该文档将被跳过。

让我们考虑上一个示例中的三个文档。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 
}

让我们看一个例子，其中查询返回所有家庭文档，其中第一个孩子的成绩在1-5之间(包括1-5)。

返回家庭文件

以下是使用BETWEEN关键字然后使用AND逻辑运算符。

SELECT * 
FROM Families.children[0] c 
WHERE c.grade BETWEEN 1 AND 5

执行上述查询后，将产生以下输出。

[ 
   { 
      "givenName": "Michelle", 
      "gender": "female", 
      "grade": 1 
   }, 
    
   { 
      "firstName": "Henriette Thaulow", 
      "gender": "female", 
      "grade": 5, 
        
      "pets": [ 
         { 
            "givenName": "Fluffy",
            "type": "Rabbit" 
         } 
      ] 
   } 
]

要显示超出上一示例范围的成绩，请使用NOT BETWEEN，如以下查询所示。

SELECT * 
FROM Families.children[0] c 
WHERE c.grade NOT BETWEEN 1 AND 5

执行此查询时。它产生以下输出。

[ 
   { 
      "familyName": "Merriam", 
      "givenName": "Jesse", 
      "gender": "female", 
      "grade": 6, 
        
      "pets": [ 
         { 
            "givenName": "Charlie Brown", 
            "type": "Dog" 
         }, 
            
         { 
            "givenName": "Tiger", 
            "type": "Cat" 
         },
            
         {
            "givenName": "Princess", 
            "type": "Cat" 
         } 
      ] 
   }
]