php fusion 2 tableaux basés sur la même clé

Question

spécifique que j'ai 2 tableaux en langage PHP:

Array 
(
    [0] => Array 
     (
      [amount] => 21600.00 
      [rows] => 2 
      [student_id] => 1 
     ) 

) 

et

Array 
(
    [0] => Array 
     (
      [amount] => 541990.00 
      [rows] => 512 
      [student_id] => 1 
     ) 

    [1] => Array 
     (
      [amount] => 347480.00 
      [rows] => 281 
      [student_id] => 2 
     ) 

    [2] => Array 
     (
      [amount] => 507400.00 
      [rows] => 214 
      [student_id] => 3 
     ) 
) 

Je veux fusionner les deux tableaux en fonction de la même valeur student_id, donc je attendre le résultat sera comme ceci:

Array 
(
    [0] => Array 
     (
      [amount] => 563590.00 
      [rows] => 514 
      [student_id] => 1 
     ) 

    [1] => Array 
     (
      [amount] => 347480.00 
      [rows] => 281 
      [student_id] => 2 
     ) 

    [2] => Array 
     (
      [amount] => 507400.00 
      [rows] => 214 
      [student_id] => 3 
     ) 
) 

J'ai essayé array_merge et array_merge_recursive mais ils ne me donne pas t il attend le résultat, merci!

Answer 1

est ici simple code pour résoudre votre problème,

count($arr) > count($arr0) ? ($greater = $arr AND $smaller = $arr0) : ($smaller = $arr AND $greater = $arr0); 
foreach ($greater as $key => &$value) { 
    foreach ($smaller as $key1 => &$value1) { 
     if($value['student_id'] == $value1['student_id']){ 
      $value['amount'] +=$value1['amount']; 
      $value['rows'] +=$value1['rows']; 
     } 
    } 
} 

Vérifiez la sortie here

Answer 2

Le commentaire sur la combinaison des requêtes est probablement la meilleure approche.

SELECT student_id, sum(amount) as amount, sum(rows) as rows 
from students 
group by student_id; 

Toutefois, si vous ne pouvez pas le faire via une requête, PHP ne pas ajouter nativement les valeurs de tableau ensemble (il n'a pas de sens)

Voici ce que vous devez faire

function arrayMergeMatch(&$a, &$b) 
{ 
    foreach ($a as $key => $value) { 
     if (array_key_exists($key, $b)) { 
      // there's a matching index in both a & b 
      $a[$key] = [ 
       $a[$key]['amount'] += $b[$key]['amount'], 
       $a[$key]['rows'] += $b[$key]['rows'], 
       $a[$key]['student_id'], 
      ]; 
     } 
    } 
} 

$firstArray = $secondArray = []; 

$firstArray[0] = [ 
    'amount' => 21600.00, 
    'rows' => 2, 
    'student_id' => 1 
]; 


$secondArray[0] = [ 
    'amount' => 541990.00, 
    'rows' => 512, 
    'student_id' => 1, 
]; 

$secondArray[1] = [ 
    'amount' => 347480.00, 
    'rows' => 281, 
    'student_id' => 2, 
]; 

$secondArray[2] = [ 
    'amount' => 507400.00, 
    'rows' => 214, 
    'student_id' => 3, 
]; 

$firstArrayLength = count($x); 
$secondArrayLength = count($y); 

$combinedArray = null; 

if ($firstArrayLength > $secondArrayLength) { 
    // loop through x checking to see if there's a matching y 
    arrayMergeMatch($firstArray, $secondArray); 
    $combinedArray = $firstArray; 
} 
else { 
    // y is longer than or equal to x, so loop through y, looking for matching 
    // index in x 
    arrayMergeMatch($secondArray, $firstArray); 
    $combinedArray = $secondArray; 
} 

print_r($combinedArray);