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$dayOfWeek
Amazon DocumentDB 中的$dayOfWeek运算符从给定的日期字段中提取一周中的某一天。它以 1（星期日）和 7（星期六）之间的数字返回一周中的某一天，这与 MongoDB 中的行为相同。
参数
示例（MongoDB 外壳）
此示例演示如何使用$dayOfWeek运算符从weather集合中的date字段中提取星期几。
创建示例文档
db.weather.insertMany([
{
"temperature": 97.5,
"humidity": 0.60,
"date": new Date("2023-04-01")
},
{
"temperature": 95.2,
"humidity": 0.55,
"date": new Date("2023-04-02")
},
{
"temperature": 92.8,
"humidity": 0.65,
"date": new Date("2023-04-03")
}
]);
查询示例
db.weather.aggregate([
{
$project: {
dayOfWeek: { $dayOfWeek: "$date" }
}
}
]).pretty();
输出
{ "_id" : ObjectId("64272c6663f4f8ce422c2d91"), "dayOfWeek" : 7 }
{ "_id" : ObjectId("64272c6663f4f8ce422c2d92"), "dayOfWeek" : 1 }
{ "_id" : ObjectId("64272c6663f4f8ce422c2d93"), "dayOfWeek" : 2 }
代码示例
要查看使用该$dayOfWeek命令的代码示例，请选择要使用的语言的选项卡：
- Node.js
-
const { MongoClient } = require('mongodb');
async function main() {
const client = await MongoClient.connect('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
const db = client.db('test');
const collection = db.collection('weather');
const result = await collection.aggregate([
{
$project: {
dayOfWeek: { $dayOfWeek: '$date' }
}
}
]).toArray();
console.log(result);
await client.close();
}
main();
- Python
-
from pymongo import MongoClient
def main():
client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
db = client.test
collection = db.weather
result = list(collection.aggregate([
{
'$project': {
'dayOfWeek': { '$dayOfWeek': '$date' }
}
}
]))
print(result)
client.close()
if __name__ == '__main__':
main()
