Update Operators (original) (raw)

The following modifiers are available for use in update operations, for example, in db.collection.updateMany() anddb.collection.findAndModify().

You can use update operators for deployments hosted in the following environments:

MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud
MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB

Specify the operator expression in a document of the form:


{

   <operator1>: { <field1>: <value1>, ... },

   <operator2>: { <field2>: <value2>, ... },

   ...

}

Note

For details on a specific operator, including syntax and examples, click on the link to the operator's reference page.

Starting in MongoDB 5.0, update operators process document fields with string-based names in lexicographic order. Fields with numeric names are processed in numeric order.

Consider this example $set command:


{ $set: { "a.2": <new value>, "a.10": <new value>, } }

In MongoDB 5.0 and later, "a.2" is processed before "a.10"because 2 comes before 10 in numeric order.

Name	Description
$currentDate	Sets the value of a field to current date, either as a Date or a Timestamp.
$inc	Increments the value of the field by the specified amount.
$min	Only updates the field if the specified value is less than the existing field value.
$max	Only updates the field if the specified value is greater than the existing field value.
$mul	Multiplies the value of the field by the specified amount.
$rename	Renames a field.
$set	Sets the value of a field in a document.
$setOnInsert	Sets the value of a field if an update results in an insert of a document. Has no effect on update operations that modify existing documents.
$unset	Removes the specified field from a document.

Name	Description
$	Acts as a placeholder to update the first element that matches the query condition.
$[]	Acts as a placeholder to update all elements in an array for the documents that match the query condition.
$[]	Acts as a placeholder to update all elements that match the arrayFilters condition for the documents that match the query condition.
$addToSet	Adds elements to an array only if they do not already exist in the set.
$pop	Removes the first or last item of an array.
$pull	Removes all array elements that match a specified query.
$push	Adds an item to an array.
$pullAll	Removes all matching values from an array.

Name	Description
$each	Modifies the $push and $addToSet operators to append multiple items for array updates.
$position	Modifies the $push operator to specify the position in the array to add elements.
$slice	Modifies the $push operator to limit the size of updated arrays.
$sort	Modifies the $push operator to reorder documents stored in an array.

Name	Description
$bit	Performs bitwise AND, OR, and XOR updates of integer values.