Find MongoDB records where array field is not empty

Today in this article we will see how to Find MongoDB records where array field is not empty or empty.

Recently I was trying to find all the records where the array field has more than documents. After the initial trivial, I found there is no direct query but was able to find a query that helped me address this requirement easily.

Below is a sample JSON where array order is defined as an array type.

Array order has 1 to 3 items in the collection.

We will build a query to find all the items where the array size is greater than 1.

Find MongoDB records where array field is not empty using $ne

Query

{<array field>: {$type:'array', $ne: [] }}

Example

{order: {$type: 'array', $ne: []}}

The above query verifies for the array “order” field is not empty.

The above query also means to return all the MongoDB documents where the array has at least 1 element existing.

In our above example, The below query gives us results for array size 1 or 2 or more as below,

Find MongoDB records where array field is empty using $eq

Query

{<array field>: {$type:'array', $eq: [] }}

Example

{order: {$type: 'array', $eq: []}}

Alternatively, you can also use the below query to find all the documents where the array field is not empty.

{'order.0': {$exists: true}}

The above query will return all the records where the array size is greater than or equal to 1

Do you have any comments or ideas or any better suggestions to share?

Please sound off your comments below.

Happy Coding !!

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