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" ] }
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