How to output or concatenate 2 json in php?

Question

PHP

There are 2 json by type:

"item":
[{      "id": "550",
      "name": "Серега"
}]

And second json :

"item":
[{      "id": "550",
       "city": "LA"
}].

Actually, how to display them in one cycle? So that the missing keys and values ​​\u200b\u200bare substituted by id, or bring them to the form:

"item":
        [{      "id": "550",
                "name": "Серега",
                "city": "LA"
        }].

Answer 1

First, convert both to arrays.
Then in one you need to replace the keys with the key from the id field
Then run the second one through the forych and add the fields from the first one by the key