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DocumentDB SQL – Order By Clause



Microsoft Azure DocumentDB supports querying documents using SQL over JSON documents. You can sort documents in the collection on numbers and strings using an ORDER BY clause in your query. The clause can include an optional ASC/DESC argument to specify the order in which results must be retrieved.

We will consider the same documents as in the previous examples.

Following is the AndersenFamily document.

{ 
   "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 
}

Following is the SmithFamily document.

{ 
   "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 
} 

Following is the WakefieldFamily document.

{ 
   "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 
} 

Let’s take a look at a simple example.

Order By Clause

Following is the query which contains the ORDER BY keyword.

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

When the above query is executed, it produces the following output.

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

Let’s consider another simple example.

Order By Clauses

Following is the query which contains the ORDER BY keyword and DESC optional keyword.

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

When the above query is executed, it will produce the following output.

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

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