JavaScript: how to get Unique data from an array

Nowadays we often deal a lot of JSON data, and array of data objects. What is the best way of filtering unique data of a data field/member property? With JavaScript latest ES6 and spread operator it can be done with just 1 line of javascript.

var data=[] ; //sample array fill up data with 10000 rows,

var uniqueCustomer=[…new Set(data.map(a=>a.customerID))];

Above will create a unique customerID from each of the record in data using customerID as property.

If the array contains no objects and property, data.map is no longer required.

Explanation:

1. data.map, return customerID as array
2. new Set, create a Set object that cannot be duplicate, those customerID that is duplicate will be discarded
3. spread operator, apply new set created as a new array.