鑑於一個具有值的陣列,如何找到匹配 MongoDB 查詢的文件?


對於特定文件,請使用 MongoDB $in。讓我們建立一個包含文件的集合 −

> db.demo511.insertOne({"ListOfProject":["Library Management System","Hospital
Management System"]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e88473a987b6e0e9d18f585")
}
> db.demo511.insertOne({"ListOfProject":["Online Web Tracking","Library Management
System"]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e884751987b6e0e9d18f586")
}
> db.demo511.insertOne({"ListOfProject":["Online Shopping Cart","Hospital Management
System"]});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e884776987b6e0e9d18f587")
}

藉助 find() 方法顯示集合中的所有文件 −

> db.demo511.find();

這將產生以下輸出 −

{ "_id" : ObjectId("5e88473a987b6e0e9d18f585"), "ListOfProject" : [ "Library Management
System", "Hospital Management System" ] }
{ "_id" : ObjectId("5e884751987b6e0e9d18f586"), "ListOfProject" : [ "Online Web Tracking",
"Library Management System" ] }
{ "_id" : ObjectId("5e884776987b6e0e9d18f587"), "ListOfProject" : [ "Online Shopping Cart",
"Hospital Management System" ] }

以下是對查詢匹配文件的查詢 −

> db.demo511.find({ "ListOfProject":{$in:["Hospital Management System","Online Shopping Cart"]}});

這將產生以下輸出 −

{ "_id" : ObjectId("5e88473a987b6e0e9d18f585"), "ListOfProject" : [ "Library Management
System", "Hospital Management System" ] }
{ "_id" : ObjectId("5e884776987b6e0e9d18f587"), "ListOfProject" : [ "Online Shopping Cart",
"Hospital Management System" ] }

最後更新時間:13-May-2020

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