Php Group array by value and count group item [duplicate] - php

Question

This question already has answers here:
How to count array with group by
(2 answers)
Closed 4 months ago.
I am creating a notification system. That results shown below returns all notifications for a particular user. I want to group the array by 'notify_id' and also count each item in a group.
Such that I'll have :
"Jack Bill is now following you", John Doe commented on your post 2",
"John Doe and 2 others commented on your post 1"
Array ( [0] =>
Array ( [id] => 1
[user_id] => 10
[type] => follow
[notify_id] => 13
[notify_date] => 1483444712
[firstname] => Jack
[surname] => Bill
[picture] => )
[1] =>
Array ( [id] => 10
[user_id] => 10
[type] => comment
[notify_id] => 2
[notify_date] => 1482159309
[firstname] => John
[surname] => Doe
[picture] => )
[2] =>
Array ( [id] => 8
[user_id] => 10
[type] => comment
[notify_id] => 1
[notify_date] => 1482159219
[firstname] => John
[surname] => Doe
[picture] => )
[3] =>
Array ( [id] => 6
[user_id] => 16
[type] => comment
[notify_id] => 1
[notify_date] => 1482159129
[firstname] => James
[surname] => Canon
[picture] => )
[4] =>
Array ( [id] => 5
[user_id] => 14
[type] => comment
[notify_id] => 1
[notify_date] => 1482159079
[firstname] => Sharon
[surname] => Abba
[picture] => ) )

Answer 1

You have two questions, I will try to answer both of them:
I want to group the array by 'notify_id'...
Assuming your array name is $a:
$return = array();
foreach($a as $val) {
if (!isset($return[$val['notify_id']])) {
$return[$val['notify_id']] = array();
}
$return[$val['notify_id']][] = $val;
}
print_r($return); // <-- Your array is grouped by notify_id
... and also count each item in a group.
Now you have your grouped by notify_id in $return so:
foreach($return as $k => $v) {
echo count($v) . ' values are present for notify #' . $k;
// It will display something like: 10 values are present for notify #1
}
Hope it will help, good luck!