JSON comparison operators

A number of different comparison operators are supported.

equality comparison operator

The following example uses the equality comparison operator:

{"name":"Joe"}

$ne (inequality comparator operator)

The following example uses the inequality comparator operator:

{"age":{"$ne":3}}

$in

The following example uses the $in operator to match at least one value in a set:

{"age":{"$in":[1,2,3,4,5]}}

You cannot use the $in operator, or the “in” operator in a index if the array contains different data types.

Do not use different types for the same field, as shown in the following incorrect example:

{"age":{"$in":[1,2,"A",3,4,5]}}

$nin

The following example uses the $nin operator to match to no values in a set, which is also referred to as the "not in" comparison operator:

{"age":{"$nin":[1,2,3,4]}}

$lt

The following example uses the $lt operator, which is also referred to as the "less than" comparison operator:

{"age":{"$lt":3}}

$lte

The following example uses the $lte operator, which is also referred to as the “less than or equals" operator:

{"age":{"$lte":3}}

$gt

The following example uses the $gt operator, which is also referred to as the “greater than" operator:

{"age":{"$gt":3}}

$gte

The following example uses the $gte operator, which is also referred to as the “greater than or equals" operator:

{"age":{"$gte":3}}

$regex (regular expression predicate)

The following example uses the regular expression predicate ($regex):

{"name":{"$regex":/^a.*\/}}