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MongoDB – Logical Query Operators

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MongoDB supports logical query operators. These operators are used for filtering the data and getting precise results based on the given conditions. The following table contains the comparison query operators:

Operator Description
$and It is used to join query clauses with a logical AND and return all documents that match the given conditions of both clauses.
$or It is used to join query clauses with a logical OR and return all documents that match the given conditions of either clause.
$not It is used to invert the effect of the query expressions and return documents that does not match the query expression.
$nor It is used to join query clauses with a logical NOR and return all documents that fail to match both clauses.

In the following examples, we are working with:

Database: GeeksforGeeks
Collection: contributor
Document: three documents that contain the details of the contributors in the form of field-value pairs.

Matching values using $and operator:

In this example, we are retrieving only those employee’s documents whose branch is CSE and joiningYear is 2018.




db.contributor.find({$and: [{branch: "CSE"}, {joiningYear: 2018}]}).pretty()


Matching values using $nor operator:

In this example, we are retrieving only those employee’s documents whose salary is not 3000 and whose branch is not ECE.




db.contributor.find({$nor: [{salary: 3000}, {branch: "ECE"}]}).pretty()


Matching values using $or operator:

In this example, we are retrieving only those employee’s documents whose branch is ECE or joiningYear is 2017.




db.contributor.find({$or: [{branch: "ECE"}, {joiningYear: 2017}]}).pretty()


Matching values using $not operator:

In this example, we are retrieving only those employee’s documents whose salary is not greater than 2000.




db.contributor.find({salary: {$not: {$gt: 2000}}}).pretty()




Last Updated : 10 May, 2020
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