有什么办法可以跳过MongoDB中的某些文档？
是的，您可以跳过skip()在MongoDB中使用的某些文档。使用limit()以显示你有多少个文件要显示跳过一些后。让我们创建一个包含文档的集合-
> db.demo682.insertOne({FirstName:"John"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462a804263e90dac94402")
}
> db.demo682.insertOne({FirstName:"Sam"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462ac04263e90dac94403")
}
> db.demo682.insertOne({FirstName:"Bob"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462af04263e90dac94404")
}
> db.demo682.insertOne({FirstName:"David"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462b304263e90dac94405")
}
> db.demo682.insertOne({FirstName:"Adam"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462ba04263e90dac94406")
}
> db.demo682.insertOne({FirstName:"Chris"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462be04263e90dac94407")
}
> db.demo682.insertOne({FirstName:"Carol"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea462c404263e90dac94408")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo682.find();
这将产生以下输出-
{ "_id" : ObjectId("5ea462a804263e90dac94402"), "FirstName" : "John" }
{ "_id" : ObjectId("5ea462ac04263e90dac94403"), "FirstName" : "Sam" }
{ "_id" : ObjectId("5ea462af04263e90dac94404"), "FirstName" : "Bob" }
{ "_id" : ObjectId("5ea462b304263e90dac94405"), "FirstName" : "David" }
{ "_id" : ObjectId("5ea462ba04263e90dac94406"), "FirstName" : "Adam" }
{ "_id" : ObjectId("5ea462be04263e90dac94407"), "FirstName" : "Chris" }
{ "_id" : ObjectId("5ea462c404263e90dac94408"), "FirstName" : "Carol" }以下是跳过3个文档并显示2的查询-
> db.demo682.find().skip(3).limit(2);
这将产生以下输出-
{ "_id" : ObjectId("5ea462b304263e90dac94405"), "FirstName" : "David" }
{ "_id" : ObjectId("5ea462ba04263e90dac94406"), "FirstName" : "Adam" }