How to grouped values in object?

Question

I wrote a function that allows you to group values in an object, but it doesn't work quite right

This is my varation

const response = Object.values(
      footerMenu.reduce((acc, key) => {
        const { databaseId, parentDatabaseId } = key;
        acc[parentDatabaseId] = (acc[parentDatabaseId] || []).concat(key);
        return acc;
      }, {})
    );

example data:

[{parentDatabase: 0, databaseId: 5728}, {parentDatabseId: 5728, databaseId: 5762}....{parentDatabse: 0, databaseId: 4532}, {parentDatabaseId: 4532, databaseId: 3221} ...]

how to group an item so that parent Database Id == 0 has its own items that relate to it

Answer 1

you have to perform a simple manipulation with the array — group the items by parentDatabaseId

The usual way is by invoking the array.reduce() method with the right callback function:

let array=[{parentDatabase: 0, databaseId: 5728}, {parentDatabase: 5728, databaseId: 5762},{parentDatabase: 0, databaseId: 4532}, {parentDatabase: 4532, databaseId: 3221} ]

const groupByDbId = array.reduce((group, item) => {
  const { parentDatabase } = item;
  group[parentDatabase] = group[parentDatabase] ?? [];
  group[parentDatabase].push(item);
  return group;
}, {});

console.log(JSON.stringify(groupByDbId, null, 2));