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$isNumber - Amazon DocumentDB
Example (MongoDB Shell)Code examples

$isNumber

New from version 8.0.1.

The $isNumber operator in Amazon DocumentDB returns a boolean indicating whether a given expression resolves to a numeric type (integer, decimal, double, long). Note that arrays are not considered numeric, even if all elements in the array are numbers. For example, $isNumber applied to the value [1, 2, 3] returns false.

Parameters

  • expression: Any expression to check whether it resolves to a numeric type.

Example (MongoDB Shell)

The following example shows how to use the $isNumber operator to check whether field values are numeric.

Create sample documents

db.data.insertMany([
  {_id: 1, value: 42},
  {_id: 2, value: "hello"},
  {_id: 3, value: 3.14},
  {_id: 4, value: null}
]);

Query example

db.data.aggregate([
  { $project: { isNum: { $isNumber: "$value" } } }
]);

Output

[
  {_id: 1, isNum: true},
  {_id: 2, isNum: false},
  {_id: 3, isNum: true},
  {_id: 4, isNum: false}
]

Code examples

To view a code example for using the $isNumber operator, choose the tab for the language that you want to use:

Node.js
const { MongoClient } = require('mongodb');

async function example() {
  const client = new MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
  try {
    await client.connect();
    const db = client.db('test');
    const collection = db.collection('data');
    const result = await collection.aggregate([
      { $project: { isNum: { $isNumber: "$value" } } }
    ]).toArray();
    console.log(result);
  } finally {
    await client.close();
  }
}
example();
Python
from pymongo import MongoClient

def example():
    client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
    try:
        db = client['test']
        collection = db['data']
        result = list(collection.aggregate([
            {'$project': {'isNum': {'$isNumber': '$value'}}}
        ]))
        print(result)
    finally:
        client.close()

example()