$pull Operator Examples

Let’s look at some examples of the $pull operator in MongoDB.

In the following examples, we are working with:

Database: w3wiki 
Collection: contributor 
Document: two documents that contain the details of the contributor in the form of field-value pairs.

Removing all the elements that equal to the specified value Example

In this example, we are removing the specified elements, i.e., [“C#”, “Perl”] from the language field.

Query:

db.contributor.update({},
... {$pull: {language: {$in: ["C#", "Perl"]}}},
... {multi: true})

Removing all the elements that match the specified condition example

In this example, we are removing semester marks that are less than and equal to ($lte) 73 from the personal.semesterMarks field in the document that matches the specified condition, i.e., name: “Rohit”.

Query:

db.contributor.update({name: "Rohit"}, 
                      {$pull: {"personal.semesterMarks": {$lte: 75}}})

Removing elements from the array of documents example

In this example, we are removing language: “Java” and tArticles: 50 items from the array of documents, i.e., articles field.

Query:

db.contributor.update({}, 
... {$pull: {articles: {language: "Java", tArticles: 50}}}, 
... {multi: true})

Output:

MongoDB $pull operator removes all the instances of the value that matches the specified condition from the existing array within the document.