Question

Here are my two arrays:

$array1 =( [0] => Array ( [row_id] => 237 [comment] => 'hello0' )
           [1] => Array ( [row_id] => 5 [comment] => 'hello1' ) 
           [2] => Array ( [row_id] => 6 [comment] => 'hello2' ) );

$array2= ( [0] => Array ( [row_id] => 5 [vote] => 1 ) 
           [1] => Array ( [row_id] => 7 [vote] => 1 ) 
           [2] => Array ( [row_id] => 237 [vote] => 0 ) );

I’d like to match $array1 and $array2 on [row_id] and add $array2‘s
[vote] key/value pairs to $array1 where $array1[row_id]=$array2[row_id]

This is how I’d like the output to be:

$array1 =( [0] => Array ( [row_id] => 237 [comment] => 'hello0' [vote] => 0  )
           [1] => Array ( [row_id] => 5 [comment] => 'hello1' [vote] => 1 ) 
           [2] => Array ( [row_id] => 6 [comment] => 'hello2' [vote] => 1 ) );

I’m sure there are many ways to do this, so thoughts on the fastest computationally would also be appreciated!

Answer 1

foreach($array1 as $key1=>$value1)
{
  foreach($array2 as $key2=>$value2)
  {
     if($value1['row_id']==$value2['row_id'])
     {
         $value1['vote'] = $value2['vote'];
         $result[$key1][]=$value1;
     }
 }
}

$result is what you need!