JSFiddle - React, Tailwind, and code Playground

by A A

JavaScript

let stat = [
{
    "_id": {
      "$oid": "5d9a16764f66ef0017a738ee"
    },
    "user": "tVH3U5Va4cBFiATvAACD",
    "team": "team1",
    "question": "5d98c7109d0e1d0017e3d31f",
    "date": {
      "$date": "2019-10-06T16:29:40.240Z"
    },
    "correct": "true",
    "ownId": "4",
    "blockId": "1"
},
{
    "_id": {
      "$oid": "5d9a167c4f66ef0017a738ef"
    },
    "user": "tVH3U5Va4cBFiATvAACD",
    "team": "team1",
    "question": "5d98c7109d0e1d0017e3d31f",
    "date": {
      "$date": "2019-10-06T16:29:46.694Z"
    },
    "correct": "true",
    "ownId": "4",
    "blockId": "1"
},
{
    "_id": {
      "$oid": "5d9a16824f66ef0017a738f0"
    },
    "user": "tVH3U5Va4cBFiATvAACD",
    "team": "team1",
    "question": "5d98c7109d0e1d0017e3d31e",
    "date": {
      "$date": "2019-10-06T16:29:52.900Z"
    },
    "correct": "true",
    "ownId": "5",
    "blockId": "1"
}]

let unique = [];

stat.forEach(function(item){
  var i = unique.findIndex(x => x.user == item.user);
  if(i <= -1){
    unique.push({id: item._id, user: item.user});
  }
});

console.log("unique", unique)