How to Find a Specific Document With Array in MongoDB

1. the find() Method in MongoDB
2. Find a Specific Document From a Collection in MongoDB

In MongoDB, a field in a document may contain some more data, something like sub-items.

In this article, we will see how we can search a specific document based on the sub-items of a field. Also, we will see an example relevant to the topic to make it easier.

the find() Method in MongoDB

We use the built-in method find() to search specific documents from a collection based on specific criteria. Now, we need to pass a parameter that searches specific elements based on the sub-item array.

The general syntax for the parameter will be:

"field.item" : 'value'

Note: Please check if you are in the right collection. To switch on a specific collection, use the command use YourCollection.

Find a Specific Document From a Collection in MongoDB

In our below example, we will illustrate how we can find a document from a collection based on the array of items. But first, let’s consider that we have the below documents in our collection:

{
    _id: ObjectId("637524953f80c4973e1f16b6"),
    sl: 1,
    Name: 'Ron',
    List: {
        Element_1: 'A',
        Element_2: '3'
        }
}
{
    _id: ObjectId("637524953f80c4973e1f16b7"),
    sl: 2,
    Name: 'Caron',
    List: {
        Element_1: 'A',
        Element_2: '3'
        }
}

As you can see above, the field List contains an array of items as a sub-item. Now, we will find a specific document based on these sub-items.

Now, the command for this purpose will look like this:

db.mycolletion.find({ "List.Element_1" : "A" })

After running the above command, you will get the below output in your console.

{
    _id: ObjectId("637524953f80c4973e1f16b6"),
    sl: 1,
    Name: 'Ron',
    List: {
        Element_1: 'A',
        Element_2: '3'
        }
}

Please note that the commands shown in this article are for the MongoDB database and the command needs to be run on the MongoDB console.