DocumentDB 排序记录
Microsoft Azure DocumentDB 支持通过 JSON 文档使用 SQL 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。
让我们看一下以下示例，其中有一个 JSON 文档。
{
"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
}
]
}
以下是按降序对结果进行排序的 SQL 查询。
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
执行上述查询后，您将收到以下输出。
[
{
"description": "Grapes, red or green (European type, such as Thompson
seedless), raw",
"foodGroup": "Fruits and Fruit Juices",
"servingDescription": "NLEA serving",
"servingWeight": 126
}
]
