آرایه زیر یک نمونه از آرایه ای است که من دارم. من می خوام که آرایه هایی که دارای id یکسان است درون cart_details توی cart_details باشن و بعد اینها با آرایه اصلی خودشون یعنی اون آرایه ای که cart_details بهش تعلق دارد.
Array
(
[0] => Array
(
[_edd_payment_user_id] => 2
[_edd_payment_meta] =>
[_edd_payment_gateway] => manual
[_edd_payment_user_email] => Aligh.Pro@gmail.com
[_edd_payment_user_ip] => ::1
[_edd_payment_purchase_key] => 246046b9340e146b6713f1965e9c0f73
[_edd_payment_mode] => live
[_edd_payment_tax_rate] => 0
[_edd_payment_customer_id] => 2
[_edd_payment_total] => 0
[_edd_payment_tax] => 0
[_edd_completed_date] => 2018-01-15 16:17:49
[_edd_complete_actions_run] => 1516036721
[key] => 246046b9340e146b6713f1965e9c0f73
[email] => Aligh.Pro@gmail.com
[date] => 2018-01-15 16:17:48
[user_info] => Array
(
[id] => 2
[email] => Aligh.Pro@gmail.com
[first_name] => مهدی یعقوبخانی
[discount] => none
[last_name] => یعقوبخانی
)

[downloads] => Array
(
[0] => Array
(
[id] => 44
[quantity] => 1
[options] => Array
(
[quantity] => 1
[price_id] => 2
)

)

)

[cart_details] => Array
(
[0] => Array
(
[name] => دانلود دو
[id] => 44
[item_number] => Array
(
[id] => 44
[quantity] => 1
[options] => Array
(
[quantity] => 1
[price_id] => 2
)

)

[item_price] => 0
[quantity] => 1
[discount] => 0
[subtotal] => 0
[tax] => 0
[fees] => Array
(
)

[price] => 0
)

)

[fees] => Array
(
)

[currency] => RIAL
)

[1] => Array
(
[_edd_payment_user_id] => 2
[_edd_payment_meta] =>
[_edd_payment_gateway] => manual
[_edd_payment_user_email] => Aligh.Pro@gmail.com
[_edd_payment_user_ip] => ::1
[_edd_payment_purchase_key] => cfa3b172a68303ded952e84174854c40
[_edd_payment_mode] => live
[_edd_payment_tax_rate] => 0
[_edd_payment_customer_id] => 2
[_edd_payment_total] => 0
[_edd_payment_tax] => 0
[_edd_completed_date] => 2018-01-14 12:45:41
[_edd_complete_actions_run] => 1515937582
[key] => cfa3b172a68303ded952e84174854c40
[email] => Aligh.Pro@gmail.com
[date] =>
[user_info] => Array
(
[id] => 2
[email] => Aligh.Pro@gmail.com
[first_name] => mahdi
[discount] => none
)

[downloads] => Array
(
[0] => Array
(
[id] => 35
[quantity] => 1
[options] => Array
(
[quantity] => 1
[price_id] => 1
)

)

)

[cart_details] => Array
(
[0] => Array
(
[name] => دانلود یک
[id] => 35
[item_number] => Array
(
[id] => 35
[quantity] => 1
[options] => Array
(
[quantity] => 1
[price_id] => 1
)

)

[item_price] => 0
[quantity] => 1
[discount] => 0
[subtotal] => 0
[tax] => 0
[fees] => Array
(
)

[price] => 0
),
[1] => Array
(
[name] => دانلود یک
[id] => 36
[item_number] => Array
(
[id] => 36
[quantity] => 1
[options] => Array
(
[quantity] => 1
[price_id] => 2
)

)

[item_price] => 0
[quantity] => 1
[discount] => 0
[subtotal] => 0
[tax] => 0
[fees] => Array
(
)

[price] => 0
)

)

[fees] => Array
(
)

[currency] => RIAL
)