Back to DocumentationMQL Documentation

$not

The `$not` operator performs a logical NOT operation on a specified expression and selects documents that don't match the expression.

Syntax

{
    field: {
        $not: {
            <operator-expression>
        }
    }
}

Parameters

operator-expressionobjectrequired

The expression to negate

Examples

Find stores with staff not equal to specific value

This query retrieves stores where the number of full-time staff isn't equal to 5 using the `$not` operator with $eq. It returns only the `name` and `staff` fields for up to two such matching documents.

Query:

db.stores.find({
    "staff.totalStaff.fullTime": {
        $not: {
            $eq: 5
        }
    }
}, {
    "name": 1,
    "staff": 1
}).limit(2)

Output:

[
    {
        "_id": "a715ab0f-4c6e-4e9d-a812-f2fab11ce0b6",
        "name": "Lakeshore Retail | Holiday Supply Hub - Marvinfort",
        "staff": {
            "totalStaff": {
                "fullTime": 9,
                "partTime": 18
            }
        }
    },
    {
        "_id": "923d2228-6a28-4856-ac9d-77c39eaf1800",
        "name": "Lakeshore Retail | Home Decor Hub - Franciscoton",
        "staff": {
            "totalStaff": {
                "fullTime": 7,
                "partTime": 6
            }
        }
    }
]

Negate comparison condition

This query retrieves stores that don't have high sales volume (not greater than 50,000).

Query:

db.stores.aggregate([
  {
    $project: {
      name: 1,
      totalSales: "$sales.salesByCategory.totalSales",
      isNotHighVolume: {
        $not: { $gt: ["$sales.salesByCategory.totalSales", 50000] }
      },
      storeCategory: {
        $cond: [
          { $not: { $gt: ["$sales.salesByCategory.totalSales", 50000] } },
          "High Volume Store",
          "Small/Medium Store"
        ]
      }
    }
  },
  { $limit: 2 }
])

Output:

[
 {
    "_id": "905d1939-e03a-413e-a9c4-221f74055aac",
    "name": "Trey Research | Home Office Depot - Lake Freeda",
    "totalSales": [ 37978 ],
    "isNotHighVolume": false,
    "storeCategory": "Small/Medium Store"
  },
  {
    "_id": "a715ab0f-4c6e-4e9d-a812-f2fab11ce0b6",
    "name": "Lakeshore Retail | Holiday Supply Hub - Marvinfort",
    "totalSales": [ 25731 ],
    "isNotHighVolume": false,
    "storeCategory": "Small/Medium Store"
  }
]

Related