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 Method of MongoDB and the limit () method to accept a number parameter, which specifies the number of records read from MongoDB.

Syntax

The basic syntax of the limit () method is as follows:

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

Instance

The data in the Set col is as follows:

{"_ Id": ObjectId ("56066542ade2f21f36b0313a"), "title": "PHP tutorial", "description ": "PHP is a powerful server-side scripting language for creating dynamic interactive sites. "," By ":" cainiao tutorial "," url ":" http://www.runoob.com "," tags ": [" php "]," likes ": 200} {"_ id": ObjectId ("56066549ade2f21f36b0313b"), "title": "Java tutorial", "description ": "Java is a high-level programming language launched by Sun Microsystems in May 1995. "," By ":" cainiao tutorial "," url ":" http://www.runoob.com "," tags ": [" java "]," likes ": 150} {"_ id": ObjectId ("5606654fade2f21f36b0313c"), "title": "MongoDB tutorial", "description": "MongoDB is a Nosql Database", "": "cainiao tutorial", "url": "http://www.runoob.com", "tags": ["mongodb"], "likes": 100}

The above example shows two records in the query document:

> Db. col. find ({}, {"title": 1, _ id: 0 }). limit (2) {"title": "PHP tutorial"} {"title": "Java tutorial"}>

Note: If you do not specify a parameter in the limit () method, all data in the set is displayed.

MongoDB Skip () method

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

Syntax

The script syntax format of the skip () method is as follows:

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

Instance

The above instance only displays the second document data

> Db. col. find ({}, {"title": 1, _ id: 0 }). limit (1 ). skip (1) {"title": "Java tutorial"}>

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

For more MongoDB tutorials, see the following:

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