DocumentDB SQL - Order By 子句
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 子句按数字和字符串对集合中的文档进行排序。 该子句可以包含可选的 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 }
让我们看一个简单的例子。
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" } ]