Updating nested objects in MongoDB can be achieved using the $set operator in combination with the dot notation to specify the path to the nested field. However, when dealing with arrays, you may need to use the positional $ operator to update elements at a specific index¹².

Using $set with Dot Notation

When you have a nested object and you want to update a specific field within it, you can use the dot notation to traverse the object and reach the field. Here's an example:

Using Positional $ Operator

If the field you want to update is inside an array, and you know the criteria to match that item but not its position, you can use the $elemMatch operator along with the positional $ operator¹:

The positional $ operator identifies the index of the first element that matches your query conditions and allows you to update it.