Update Operators

The following modifiers are available for use in update operations, for example, in petdb.PetCollection.update() and petdb.PetCollection.update_one().

Warning

Any update operator doesn’t support nesting object query, you should only use the dot notation to specify fields.

{"$set": {"info.name": "Item 1"}} # Good
{"$set": {"info": {"name": "Item 1"}}} # Wrong

Fields

$set	Sets the value of a field in a document.
$unset	Removes the specified field from a document.
$inc	Increments the value of the field by the specified amount.
$map	Calculates and sets the value of a field depending on its current value.

Arrays

$push, $append	Adds an item to an array.
$addToSet	Adds elements to an array only if they do not already exist in the set.
$pull, $remove	Removes all array elements that match a specified query.