Question

Example: –

$arrayName = array(
  '0' => array('name' => 'a', 'id' => '123'  ),
  '1' =>  array('name' => 'b', 'id' => '123'  ), 
  '3' => array('name' => 'c', 'id' => '456'  ) 
);

Same Id value should be grouped here

Result:

$arrayName = array(
  '0' => array(
    '0' =>  array('name' => 'a', 'id' => '123'  ),
    '1' => array('name' => 'b', 'id' => '123'  ) ), 
  '1' => array('1' => array('name' => 'c', 'id' => '456'  ) );

Answer 1

Using your example set, you can simply iterate through the values, and group the data based on id. Using something like

$output = array();
foreach($arrayName as $data){
  $output[$data['id']][] = $data;
}

The output of that would be:

array(2) {
  [123]=>
  array(2) {
    [0]=>
    array(2) {
      ["name"]=>
      string(1) "a"
      ["id"]=>
      string(3) "123"
    }
    [1]=>
    array(2) {
      ["name"]=>
      string(1) "b"
      ["id"]=>
      string(3) "123"
    }
  }
  [456]=>
  array(1) {
    [0]=>
    array(2) {
      ["name"]=>
      string(1) "c"
      ["id"]=>
      string(3) "456"
    }
  }
}

If you really don’t want the id to be the key, just grab the values from that associative array.

$output = array_values($output)

array(2) {
  [0]=>
  array(2) {
    [0]=>
    array(2) {
      ["name"]=>
      string(1) "a"
      ["id"]=>
      string(3) "123"
    }
    [1]=>
    array(2) {
      ["name"]=>
      string(1) "b"
      ["id"]=>
      string(3) "123"
    }
  }
  [1]=>
  array(1) {
    [0]=>
    array(2) {
      ["name"]=>
      string(1) "c"
      ["id"]=>
      string(3) "456"
    }
  }
}

Note: There’s likely a better way to do this, using some of the other array functions; however, this shows the basic logic.