MongoDB Query Language (MQL) Field Update Operators
$currentDate
Sets the value of a field to the current date, either as a Date or a timestamp, useful for tracking document modifications.
$inc
Increments the value of a field by a specified amount, creating the field if it doesn't exist, accepting positive and negative values.
$max
Updates a field only if the specified value is greater than the current field value, useful for maintaining maximum values.
$min
Updates a field only if the specified value is less than the current field value, useful for maintaining minimum values.
$mul
Multiplies the value of a field by a specified number, creating the field with value zero if it doesn't exist, useful for scaling and percentage operations.
$rename
Renames fields in documents during update operations, removing the old field name and creating a new field with the same value.
$set
Sets the value of fields in documents, creating new fields if they don't exist or updating existing field values.
$setOnInsert
Sets field values only when an upsert operation results in inserting a new document, having no effect when updating existing documents.
$unset
Removes specified fields from documents, effectively deleting the field and its value entirely.