$isNumber - Amazon DocumentDB
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$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 demonstrates 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()