You can increment or decrement a numeric field value as shown in the following example. An increment operation increases or decreases the current value of a field by the given amount.

To increment a numeric field value, use a POSITIVE number. To decrement a numeric field value, use a NEGATIVE number.

The Increment operation is only available for numeric fields and will only work if the Field has either been declared during a Add operation or has been updated with a Update operation. If the Field doesn’t exist, the Increment operation will fail.

Initialize Database Modules

const worqhat = require('worqhat');

var config = new worqhat.Configuration({
    apiKey: "your-api-key",
    debug: true,
    max_retries: 3,
});

worqhat.initializeApp(config);

let db = worqhat.database();

Increment Numeric Data

db.collection('NodeJSDb1').doc('de79272c-2ed3-46d9-ae93-ff195364466e').update({
    age: db.increment(10)
}).then((response) => {
    console.log(response);
}).catch((error) => {
    console.log(error);
});

Decrement Numeric Data

db.collection('NodeJSDb1').doc('de79272c-2ed3-46d9-ae93-ff195364466e').update({
    age: db.increment(-10)
}).then((response) => {
    console.log(response);
}).catch((error) => {
    console.log(error);
});