Join 2 multidimensional array - php

Question

$items = array(
array(
'id' => 0,
'name' => 'Simple Sword',
'type' => 'weapon',
'price' => 200,
'value1' => 5,
'value2' => 10,
'value3' => 0,
'value4' => 0,
'value5' => 0
),
array(
'id' => 1,
'name' => 'Iron Sword',
'type' => 'weapon',
'price' => 500,
'value1' => 0,
'value2' => 0,
'value3' => 0,
'value4' => 0,
'value5' => 0
)
);
$inventory = array(
array(
'item' => 0,
'slot' => 1,
'value1' => 0,
'value2' => 0,
'value3' => 0,
'value4' => 0,
'value5' => 0,
'equipped' => 0
),
array(
'item' => 1,
'slot' => 2,
'value1' => 0,
'value2' => 0,
'value3' => 0,
'value4' => 0,
'value5' => 0,
'equipped' => 1
)
);
What I need is to join these 2 multidimensional arrays, or take the values, keys etc from the "Items" array and put it in the Inventory array where the "item" id matches the id from the Items array. Similiar to a INNER JOIN statement in SQL. How? I can't figure it out.
Secondly, I am trying to print out the $inventory array, I tried the following, but It didn't work:
foreach ($inventory as $a) {
foreach ($a as $b) {
echo $b['item'];
}
}
It gives me no output.

Answer 1

a little help with your second problem:
foreach ($inventory as $a => $b) {
echo $b['item'];
}
}

Answer 2

As for first question Zulkhaery Basrul gave good answer. I would also consider putting break statement if relation is one-to-one:
if($val['item'] == $items[$key]['id']) {
$newarr[] = array_merge($items[$key],$val);
break;
}
As for second question:
foreach ($inventory as $invKey => $aInventoryItem) {
echo $aInventoryItem['item'] . "\n";
}

Answer 3

I think you can just do this in order to echo the item from inventory:
foreach($inventory as $inv) {
echo $inv['item'];
}

Answer 4

foreach($inventory as $key=>$val)
{
if($val['item'] == $items[$key]['id'])
{
$newarr[] = array_merge($items[$key],$val);
}
}
check $newarr[] using print_r($newarr), here the output :
Array
(
[0] => Array
(
[id] => 0
[name] => Simple Sword
[type] => weapon
[price] => 200
[value1] => 0
[value2] => 0
[value3] => 0
[value4] => 0
[value5] => 0
[item] => 0
[slot] => 1
[equipped] => 0
)
[1] => Array
(
[id] => 1
[name] => Iron Sword
[type] => weapon
[price] => 500
[value1] => 0
[value2] => 0
[value3] => 0
[value4] => 0
[value5] => 0
[item] => 1
[slot] => 2
[equipped] => 1
)
)
Second question, to print out the $inventory array:
foreach ($inventory as $a)
{
echo $a['item'];
echo $a['slot'];
echo $a['value1'];
//...etc
}

Answer 5

I believe this function is what you're looking for:
// Join Arrays on Keys
function array_join($original, $merge, $on) {
if (!is_array($on)) $on = array($on);
foreach ($merge as $right) {
foreach ($original as $index => $left) {
foreach ($on as $from_key => $to_key) {
if (!isset($original[$index][$from_key])
|| !isset($right[$to_key])
|| $original[$index][$from_key] != $right[$to_key])
continue 2;
}
$original[$index] = array_merge($left, $right);
}
}
return $original;
}
Usage for your scenario:
print_r(array_join($items, $inventory, array('id' => 'item')));
I've asked the community for help with optimizing the LEFT JOIN version of the function here (the only differences are $remove unset and array_merge): How can I optimize my array_join (simulates a LEFT JOIN) function?