如何使用LIMIT查询MongoDB？
使用limit()方法查询MongoDB。让我们创建一个包含文档的集合
> db.demo58.insertOne({"Name":"David"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e285f8fcfb11e5c34d8991f")
}
> db.demo58.insertOne({"Name":"David"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e285f93cfb11e5c34d89920")
}
> db.demo58.insertOne({"Name":"David"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e285f94cfb11e5c34d89921")
}
> db.demo58.insertOne({"Name":"Mike"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e285f99cfb11e5c34d89922")
}> db.demo58.find();
{ "_id" : ObjectId("5e285f8fcfb11e5c34d8991f"), "Name" : "David" }
{ "_id" : ObjectId("5e285f93cfb11e5c34d89920"), "Name" : "David" }
{ "_id" : ObjectId("5e285f94cfb11e5c34d89921"), "Name" : "David" }
{ "_id" : ObjectId("5e285f99cfb11e5c34d89922"), "Name" : "Mike" }> v=2;
2
> d=db.demo58.find({"Name":"David"}).limit(v+1);
{ "_id" : ObjectId("5e285f8fcfb11e5c34d8991f"), "Name" : "David" }
{ "_id" : ObjectId("5e285f93cfb11e5c34d89920"), "Name" : "David" }
{ "_id" : ObjectId("5e285f94cfb11e5c34d89921"), "Name" : "David" }
> m=d.size() > v;True