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MongoDB limit() MethodIn MongoDB, limit() method is used to limit the fields of document that you want to show. Sometimes, you have a lot of fields in collection of your database and have to retrieve only 1 or 2. In such case, limit() method is used. The MongoDB limit() method is used with find() method. Syntax: db.COLLECTION_NAME.find().limit(NUMBER) Scenario:
Consider an example which has a collection name TheDeveloperBlog. This collection has following fields within it.
[
{
Course: "Java",
details: { Duration: "6 months", Trainer: "Sonoo Jaiswal" },
Batch: [ { size: "Medium", qty: 25 } ],
category: "Programming Language"
},
{
Course: ".Net",
details: { Duration: "6 months", Trainer: "Prashant Verma" },
Batch: [ { size: "Small", qty: 5 }, { size: "Medium", qty: 10 }, ],
category: "Programming Language"
},
{
Course: "Web Designing",
details: { Duration: "3 months", Trainer: "Rashmi Desai" },
Batch: [ { size: "Small", qty: 5 }, { size: "Large", qty: 10 } ],
category: "Programming Language"
}
];
Here, you have to display only one field by using limit() method. Example
db.TheDeveloperBlog.find().limit(1) After the execution, you will get the following result Output: { "_id" : ObjectId("564dbced8e2c097d15fbb601"), "Course" : "Java", "details" : {
"Duration" : "6 months", "Trainer" : "Sonoo Jaiswal" }, "Batch" : [ { "size" :
"Medium", "qty" : 25 } ], "category" : "Programming Language" }
MongoDB skip() method
In MongoDB, skip() method is used to skip the document. It is used with find() and limit() methods. Syntaxdb.COLLECTION_NAME.find().limit(NUMBER).skip(NUMBER) Scenario:Consider here also the above discussed example. The collection TheDeveloperBlog has three documents.
[
{
Course: "Java",
details: { Duration: "6 months", Trainer: "Sonoo Jaiswal" },
Batch: [ { size: "Medium", qty: 25 } ],
category: "Programming Language"
},
{
Course: ".Net",
details: { Duration: "6 months", Trainer: "Prashant Verma" },
Batch: [ { size: "Small", qty: 5 }, { size: "Medium", qty: 10 }, ],
category: "Programming Language"
},
{
Course: "Web Designing",
details: { Duration: "3 months", Trainer: "Rashmi Desai" },
Batch: [ { size: "Small", qty: 5 }, { size: "Large", qty: 10 } ],
category: "Programming Language"
}
];
Execute the following query to retrieve only one document and skip 2 documents. Exampledb.TheDeveloperBlog.find().limit(1).skip(2) After the execution, you will get the following result Output: { "_id" : ObjectId("564dbced8e2c097d15fbb603"), "Course" : "Web Designing", "det
ails" : { "Duration" : "3 months", "Trainer" : "Rashmi Desai" }, "Batch" : [ { "
size" : "Small", "qty" : 5 }, { "size" : "Large", "qty" : 10 } ], "category" : "
Programming Language" }
As you can see, the skip() method has skipped first and second documents and shows only third document.
Next TopicMongoDB sort()
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