怎樣在 MongoDB 中透過 _id 查詢記錄?
要透過 _id 在 MongoDB 中查詢記錄,你可以使用以下語法
db.yourCollectionName.find({"_id":yourObjectId});讓我們用文件建立一個集合
> db.findRecordByIdDemo.insertOne({"CustomerName":"Larry","CustomerAge":26});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9dc2c875e2eeda1d5c3671")
}
> db.findRecordByIdDemo.insertOne({"CustomerName":"Bob","CustomerAge":20});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9dc2d175e2eeda1d5c3672")
}
> db.findRecordByIdDemo.insertOne({"CustomerName":"Carol","CustomerAge":22});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9dc2d775e2eeda1d5c3673")
}
> db.findRecordByIdDemo.insertOne({"CustomerName":"David","CustomerAge":24});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c9dc2e375e2eeda1d5c3674")
}以下是使用 find() 方法從集合中顯示所有文件的查詢
> db.findRecordByIdDemo.find().pretty();
這將生成以下輸出
{
"_id" : ObjectId("5c9dc2c875e2eeda1d5c3671"),
"CustomerName" : "Larry",
"CustomerAge" : 26
}
{
"_id" : ObjectId("5c9dc2d175e2eeda1d5c3672"),
"CustomerName" : "Bob",
"CustomerAge" : 20
}
{
"_id" : ObjectId("5c9dc2d775e2eeda1d5c3673"),
"CustomerName" : "Carol",
"CustomerAge" : 22
}
{
"_id" : ObjectId("5c9dc2e375e2eeda1d5c3674"),
"CustomerName" : "David",
"CustomerAge" : 24
}
Following is the query to find record by _id in MongoDB:
> db.findRecordByIdDemo.find({"_id":ObjectId("5c9dc2d175e2eeda1d5c3672")}).pretty();這將生成以下輸出
{
"_id" : ObjectId("5c9dc2d175e2eeda1d5c3672"),
"CustomerName" : "Bob",
"CustomerAge" : 20
}
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