Read Documents: Part 6
Explore how to use projection operators in MongoDB to retrieve specific parts of documents efficiently. Learn to apply the positional operator, $elemMatch, and $slice to control array data in query outputs, helping you manage and read documents with precision.
We'll cover the following...
We'll cover the following...
Projection operators
Projection means to select only the necessary data instead of the entire document. The projection operators are used to project the output of the query. The second argument of find functions is a projection document, and we can only define projection operators inside it.
$ operator
The $ operator is called the positional operator, and it’s used to project the first array element from the document. Below are a few points to remember about the positional operator:
- It is applied only on the
arrayfield. - It works only if the
arrayfield is included in the filter query, otherwise, it throws an error. - It only appears at the