MongoDB的大量收集和缓慢的搜索？怎么修？
为了更快地搜索，请创建索引。为此，请使用createIndex()。让我们创建一个包含文档的集合-
> db.demo661.createIndex({ListOfName:1});
{
"createdCollectionAutomatically" : true,
"numIndexesBefore" : 1,
"numIndexesAfter" : 2,
"ok" : 1
}
> db.demo661.insertOne({_id:1,ListOfName:["John","Robert","David"]});
{ "acknowledged" : true, "insertedId" : 1 }
> db.demo661.insertOne({_id:2,ListOfName:["Mike","Sam"]});
{ "acknowledged" : true, "insertedId" : 2 }
> db.demo661.insertOne({_id:3,ListOfName:["John","David","Bob"]});
{ "acknowledged" : true, "insertedId" : 3 }在find()方法的帮助下显示集合中的所有文档-
> db.demo661.find();
这将产生以下输出-
{ "_id" : 1, "ListOfName" : [ "John", "Robert", "David" ] }
{ "_id" : 2, "ListOfName" : [ "Mike", "Sam" ] }
{ "_id" : 3, "ListOfName" : [ "John", "David", "Bob" ] }以下是获取文档的查询-
> db.demo661.find({"ListOfName": {"$all":["John","David"]}});这将产生以下输出-
{ "_id" : 1, "ListOfName" : [ "John", "Robert", "David" ] }
{ "_id" : 3, "ListOfName" : [ "John", "David", "Bob" ] }