How to return json object with json array inside of it?

There's 2 way to do it:

1. If you want to keep your query, you must parse the data first before you parse it to json.

...function regroup_color($data = array()){  $ret = array();  foreach($data as $d){    $id = $d['id'];    if(!isset($ret[$id])){      $color = $d['color'];      unset($d['color']);      $ret[$id] = $d;      $ret[$id]['color'][] = $color;    }else{      $ret[$id]['color'][] = $d['color'];    }  }  return $ret;}$data = regroup_color($data);echo json_encode($data)...

Or you could just...

2. make the query 2 part, first is for get all items, second is for get the colors for it

...$query = "SELECT * FROM items";// get the data here using query above$data = {{result of query}};foreach($data as $i => $d){  $id = $d['id'];  $query = "SELECT * FROM item_color JOIN colors ON item_color.color_id = colors.id";  // get the data here using query above  $colors = {{result of query}};  foreach($colors as color){    $data[$i]['color'][] = $color['name'];  }}echo json_encode($data)...

i wanted to add also category so this is what i came with

function regroup_color($data = array(),$data2 = array()){  // array that will hold our data and we will return it later$ret = array();// fetch the data as dforeach($data as $d){  //save the id   $id = $d['id'];  //make sure no id was set  if(!isset($ret[$id])){    // save the name of the color    $color = $d['color'];    unset($d['color']);    //save all the item data    $ret[$id] = $d;    // add color to color array    $ret[$id]['color'][] = $color;  }else{    // if wa alredy did all the above things just keep adding colors to color array    $ret[$id]['color'][] = $d['color'];  }}    foreach($data2 as $d){    //save the id       $id = $d['id'];      //make sure no id was set      if(!isset($ret[$id])){        // save the name of the color        $category = $d['category'];        unset($d['category']);        $ret[$id] = $d;        $ret[$id]['category'][] = $category;      }else{        $ret[$id]['category'][] = $d['category'];      }    }

return $ret;}

result :

"22": {"id": "22","title": "my products 515151","descreption": "5454545455","price": "0.05","quantity": "2","date_added": "2021-01-29 14:37:24","primary_image": "http://localhost/ecomerce/uploads/1611927444hat.jpg","color": [  "black",  "white",  "pink",  "red",  "yellow"],"category": [  "buttom",  "hats",  "shoes"]

}