Query and Projection Operators

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MongoDB Query and Projection Operators

Comparison Query operators

Name

Description

$gt

Matches values that are greater than the value specified in the query.

$lt

Matches values that are less than the value specified in the query.

$gte

Matches values that are greater than or equal to the value specified in the query.

$lte

Matches values that are less than or equal to the value specified in the query.

$ne

Matches all values that are not equal to the value specified in the query.

$in

Matches any of the values that exist in an array specified in the query.

$nin

Matches values that do not exist in an array specified in the query.

Logical Query operators

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 expression and returns documents that do not match the query expression.

$or

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

$nor

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

Element Query operators

Name

Description

$exists

Matches documents that have the specified field.

$type

Selects documents if a field is of the specified type.

Evaluation Query operators

Name

Description

$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.

$where

Matches documents that satisfy a JavaScript expression.

Query operator Array

Name

Description

$all

Matches arrays that contain all elements specified in the query.

$elemMatch

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

$size

Selects documents if the array field is a specified size.

Projection operator

Name

Description

$

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

$elemMatch(projection)

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

$slice

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