PHP - Large Array merging by key content - php

Question

I'm currently working on a PHP project in which I need to merge 5 large arrays of arrays (around 16000 entries each) by a specific key value. With this I mean each array includes about 16000 entries, each being an array with key => value format, and I intend to merge all these arrays where the value for a given key matches. For example:
I have:
arr1=[[id=>1,name=>john,surname=>doe],[id=>2,name=>katy,surname=>johnson]];
arr2=[[id=>2,age=>23,adress=>something][id=>1,age=>43,adress=>something else]];
arr3=[[id=>1,employee_number=1234],[id=>3,employee_number=2345],[id=>2,emplyee_number=>6523]];
And plan to obtain:
arr=[[id=>1,name=>john,surname=>doe,age=43,adress=>something else],[id=>2,name=>katy,surname=>johnson,age=>23,adress=>something]];
My first attempt was to loop through every array using for loops and join the arrays when the given value for the id key was matched, but this proved highly inefficient for such a big number of entries (16000 for each array). Can someone suggest any better options to accomplish the given task?
Edit:
Even though the example has generic arrays names (arr1,arr2) the code I tried to implement was this, with the referred 5 arrays and looping through each to compare and tried to merge by the sku key value.
for($i=0;$i < sizeof($received_products); $i++){
for($j=0; $j < sizeof($received_descriptions); $j++){
for($k=0; $k < sizeof($received_multimedia); $k++){
for($l=0; $l < sizeof($received_stocks); $l++){
for($m=0; $m < sizeof($received_prices); $m++){
if(strcmp(strcmp($received_products[$i]['sku'],$received_descriptions[$j]['sku'])&&strcmp($received_multimedia[$k]['sku'],$received_stocks[$l]['sku']),$received_prices[$m]['sku'])==0){
$all_products[$i]=array_merge($received_products[$i],$received_descriptions[$j],$received_multimedia[$k],$received_stocks[$l],$received_prices[$m]);
}
}
}
}
}
}

Answer 1

You should be able to do this with two nested loops:
<?php
$arr1 = [['id' => 1, 'name' => 'john', 'surname' => 'doe'], ['id' => 2, 'name' => 'katy', 'surname' => 'johnson']];
$arr2 = [['id' => 2, 'age' => 23, 'address' => 'something'], ['id' => 1, 'age' => 43, 'address' => 'something else']];
$arr3 = [['id' => 1, 'employee_number' => 1234], ['id' => 3, 'employee_number' => 2345], ['id' => 2, 'emplyee_number' => 6523]];
$buffer = [];
// For each of the records sets...
foreach ([$arr1, $arr2, $arr3] as $currRecordSet)
{
// Loop through the records...
foreach ($currRecordSet as $currRecord)
{
// If we do not have an entry in our buffer for ths ID yet, create one
$currKey = '_' . $currRecord['id'];
if (!array_key_exists($currKey, $buffer))
{
$buffer[$currKey] = [];
}
// Merge this record with the values in the buffer
$buffer[$currKey] = array_merge($buffer[$currKey], $currRecord);
}
}
// Get the bare array of combined entries without our ugly buffer keys
$combinedRecords = array_values($buffer);
print_r($combinedRecords);