通过聚合管道实现此目标。首先让我们创建一个包含文档的集合-
> db.demo413.insertOne( ... { ... "_id": "101", ... "details": { ... "Info1": { ... Name:"Chris", ... Age:21 ... }, ... "Info2": { ... Name:"David", ... Age:23 ... } ... } ... } ... ); { "acknowledged" : true, "insertedId" : "101" }
在find()
方法的帮助下显示集合中的所有文档-
> db.demo413.find();
这将产生以下输出-
{ "_id" : "101", "details" : { "Info1" : { "Name" : "Chris", "Age" : 21 }, "Info2" : { "Name" : "David", "Age" : 23 } } }
以下是排除嵌套字段的查询-
> db.demo413.aggregate([ ... { $project: { "details" : { $objectToArray: "$details" } } }, ... { $project: { "details.v.Age" : 0} }, ... { $project: { "details" : { $arrayToObject: "$details"} } } ... ]);
这将产生以下输出-
{ "_id" : "101", "details" : { "Info1" : { "Name" : "Chris" }, "Info2" : { "Name" : "David" } } }