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$rename
Amazon DocumentDB 中的$rename運算子用於重新命名文件中的欄位。當您需要更新文件結構或使其與新的資料模型保持一致時,此運算子特別有用。
參數
-
field:要重新命名的欄位。
-
newName: 欄位的新名稱。
範例 (MongoDB Shell)
下列範例示範如何使用 $rename運算子,在將 "Date.DoW" 欄位設為 的"Date.DayOfWeek"文件中將 "DocName" 欄位重新命名為 "Document 1"。
建立範例文件
db.example.insertOne({
"DocName": "Document 1",
"Date": {
"Month": 4,
"Day": 18,
"Year": 1987,
"DoW": "Saturday"
},
"Words": 2482
})
查詢範例
db.example.update(
{ "DocName": "Document 1" },
{ $rename: { "Date.DoW": "Date.DayOfWeek" } }
)
輸出
{
"DocName": "Document 1",
"Date": {
"Month": 4,
"Day": 18,
"Year": 1987,
"DayOfWeek": "Saturday"
},
"Words": 2482
}
程式碼範例
若要檢視使用 $rename命令的程式碼範例,請選擇您要使用的語言標籤:
- Node.js
-
const { MongoClient } = require('mongodb');
async function example() {
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('example');
await collection.updateOne(
{ "DocName": "Document 1" },
{ $rename: { "Date.DoW": "Date.DayOfWeek" } }
);
const updatedDoc = await collection.findOne({ "DocName": "Document 1" });
console.log(updatedDoc);
await client.close();
}
example();
- Python
-
from pymongo import MongoClient
def example():
client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
db = client['test']
collection = db['example']
collection.update_one(
{"DocName": "Document 1"},
{"$rename": {"Date.DoW": "Date.DayOfWeek"}}
)
updated_doc = collection.find_one({"DocName": "Document 1"})
print(updated_doc)
client.close()
example()