Alright, so I have three arrays with about 65k objects in each in node.js. They all share an ID - PARCELID, SBL, and SBL20 are the same. I want to combine the objects from the different arrays into a single object that is then pushed into the final array. For whatever reason, the output I get contains 130k+ objects. This is also pretty inefficient so if there is a better way to do this, I am all ears - I have attempted to use map() though I was only able to compare two arrays, not three. I have a fourth I would like to add into the mix as well.
var final = new Array();
count=0
TaxParcels.forEach((TaxParcel) => {
TaxBills.forEach((TaxBill) => {
if (TaxParcel.PARCELID == TaxBill.SBL20) {
CodeEnforcements.forEach((CodeEnforcement) => {
if (TaxParcel.PARCELID == CodeEnforcement.SBL) {
parcel = {
ID: TaxParcel.PARCELID,
DETAILS: {
TaxParcel: TaxParcel,
TaxBill: TaxBill,
CodeEnforcement: CodeEnforcement,
},
};
final.push(parcel);
count++
}
});
}
});
});
console.log(final);
console.log(count)You can get performance gain by first creating a Map, keyed by the keys, with empty objects related to each. Then inject the objects into those objects, and filter the result to only have objects with all 3 keys:
// sample data
let TaxParcels = [{ PARCELID: 3 }, { PARCELID: 9 }, { PARCELID: 7 }];
let TaxBills = [{ SBL20: 9 }, { SBL20: 1 }, { SBL20: 3 }];
let CodeEnforcements = [{ SBL: 3 }, { SBL: 9 }, { SBL: 1 }];
// Solution
let map = new Map([...TaxParcels, ...TaxBills, ...CodeEnforcements].map(o =>
[o.PARCELID??o.SBL20??o.SBL, {}])
);
for (let o of TaxParcels) map.get(o.PARCELID).TaxParcel = o;
for (let o of TaxBills) map.get(o.SBL20).TaxBill = o;
for (let o of CodeEnforcements) map.get(o.SBL).CodeEnforcement = o;
let result = [...map.values()].filter(o => Object.keys(o).length === 3);
console.log(result);
console.log(result.length);The simplest (and maybe not most significant) way is to avoid forEach here: it iterates over the whole arrays pointlessly even after the element is found. There is no way to break forEach. It may be replaced with for-of loops with break or with find array methods. This will also eliminate duplicates. The last way example:
const TaxParcels = [{ PARCELID: 1}, { PARCELID: 2}, { PARCELID: 3}];
const TaxBills = [{ SBL20: 1}, { SBL20: 2}, { SBL20: 3}];
const CodeEnforcements = [{ SBL: 1}, { SBL: 2}, { SBL: 3}];
const final = [];
let count=0;
for (const TaxParcel of TaxParcels) {
const ID = TaxParcel.PARCELID;
const TaxBill = TaxBills.find(({ SBL20 }) => SBL20 === ID);
const CodeEnforcement = CodeEnforcements.find(({ SBL }) => SBL === ID);
if (TaxBill && CodeEnforcement) {
count++;
final.push({ ID, DETAILS: { TaxParcel, TaxBill, CodeEnforcement } });
}
}
console.log(count);
console.log(JSON.stringify(final, null, ' '));But maybe the most significant improvement is to use more appropriate id-keyed structures as in other answer here.