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MongoDB Limit and Skip methods

MongoDB Limit and Skip methods


MongoDB Limit () method

If you need to read a specified number of data records in MongoDB, you can use the Limit MongoDB method, limit () method accepts a numeric parameter that specifies the number of records read from MongoDB in.

grammar

limit () method basic syntax is as follows:

>db.COLLECTION_NAME.find().limit(NUMBER)

Examples

Col data collection are as follows:

{ "_id" : ObjectId("56066542ade2f21f36b0313a"), "title" : "PHP 教程", "description" : "PHP 是一种创建动态交互性站点的强有力的服务器端脚本语言。", "by" : "本教程", "url" : "http://www.w3big.com", "tags" : [ "php" ], "likes" : 200 }
{ "_id" : ObjectId("56066549ade2f21f36b0313b"), "title" : "Java 教程", "description" : "Java 是由Sun Microsystems公司于1995年5月推出的高级程序设计语言。", "by" : "本教程", "url" : "http://www.w3big.com", "tags" : [ "java" ], "likes" : 150 }
{ "_id" : ObjectId("5606654fade2f21f36b0313c"), "title" : "MongoDB 教程", "description" : "MongoDB 是一个 Nosql 数据库", "by" : "本教程", "url" : "http://www.w3big.com", "tags" : [ "mongodb" ], "likes" : 100 }

Examples of the above query to display the document in two records:

> db.col.find({},{"title":1,_id:0}).limit(2)
{ "title" : "PHP 教程" }
{ "title" : "Java 教程" }
>

NOTE: If you do not specify the limit () method parameters are displayed in the collection of all data.


MongoDB Skip () method

In addition we can use the limit () method to read a specified number of data, you can also use the skip () method to skip a specified number of data, skip method also accepts a numeric parameter as the number of records to skip.

grammar

skip () method script syntax is as follows:

>db.COLLECTION_NAME.find().limit(NUMBER).skip(NUMBER)

Examples

The above examples show only the second document data

>db.col.find({},{"title":1,_id:0}).limit(1).skip(1)
{ "title" : "Java 教程" }
>

NOTE: skip () method of the default parameter is 0.