Query operators

                                                     

Comparison

For comparison of different BSON type values, see the specified BSON comparison order.

Name
Description

$eq

Matches values that are equal to a specified value.

$gt

Matches values that are greater than a specified value.

$gte

Matches values that are greater than or equal to a specified value.

$in

Matches any of the values specified in an array.

$lt

Matches values that are less than a specified value.

$lte

Matches values that are less than or equal to a specified value.

$ne

Matches all values that are not equal to a specified value.

$nin

Matches none of the values specified in an array.


db.student.find({marks: {$gt:60}})

db.student.find({ city: { $in: ["delhi", "mumbai"] } })

 db.student.find({$or: [{marks:{$gt:75}},{city:"delhi"}]})


Logical

Name
Description

$and

Joins query clauses with a logical AND returns all documents that match the conditions of both clauses.

$not

Inverts the effect of a query predicate and returns documents that do not match the query predicate.

$nor

Joins query clauses with a logical NOR returns all documents that fail to match both clauses.

$or

Joins query clauses with a logical OR returns all documents that match the conditions of either clause.

Element

Name
Description

$exists

Matches documents that have the specified field.

$type

Selects documents if a field is of the specified type.

Evaluation

Name
Description

$expr

Allows use of aggregation expressions within the query language.

$jsonSchema

Validate documents against the given JSON Schema.

$mod

Performs a modulo operation on the value of a field and selects documents with a specified result.

$regex

Selects documents where values match a specified regular expression.

$text

Performs text search.

$text provides text query capabilities for self-managed (non-Atlas) deployments. For data hosted on MongoDB Atlas, MongoDB offers an improved full-text query solution, Atlas Search.

$where

Matches documents that satisfy a JavaScript expression.

Geospatial

Name
Description

$geoIntersects

Selects geometries that intersect with a GeoJSON geometry. The 2dsphere index supports $geoIntersects.

$geoWithin

Selects geometries within a bounding GeoJSON geometry. The 2dsphere and 2d indexes support $geoWithin.

$near

Returns geospatial objects in proximity to a point. Requires a geospatial index. The 2dsphere and 2d indexes support $near.

$nearSphere

Returns geospatial objects in proximity to a point on a sphere. Requires a geospatial index. The 2dsphere and 2d indexes support $nearSphere.

Array

Name
Description

$all

Matches arrays that contain all elements specified in the query.

$elemMatch

Selects documents if element in the array field matches all the specified $elemMatch conditions.

$size

Selects documents if the array field is a specified size.

Bitwise

Name
Description

$bitsAllClear

Matches numeric or binary values in which a set of bit positions all have a value of 0.

$bitsAllSet

Matches numeric or binary values in which a set of bit positions all have a value of 1.

$bitsAnyClear

Matches numeric or binary values in which any bit from a set of bit positions has a value of 0.

$bitsAnySet

Matches numeric or binary values in which any bit from a set of bit positions has a value of 1.

Projection Operators

Name
Description

$

Projects the first element in an array that matches the query condition.

$elemMatch

Projects the first element in an array that matches the specified $elemMatch condition.

$meta

Projects the document's score assigned during the $text operation.

$text provides text query capabilities for self-managed (non-Atlas) deployments. For data hosted on MongoDB Atlas, MongoDB offers an improved full-text query solution, Atlas Search.

$slice

Limits the number of elements projected from an array. Supports skip and limit slices.

Miscellaneous Operators

Name
Description

$rand

Generates a random float between 0 and 1.

$natural

A special hint that can be provided via the sort() or hint() methods that can be used to force either a forward or reverse collection scan.

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