Find value assoaction in array - php

Question

i have a multi dimension array with sub array having repeated values of 'eduHisRowId' like:
Array
(
[0] => Array
(
[eduHisRowId] => 4
[repOrderId] => 15
)
[1] => Array
(
[eduHisRowId] => 5
[repOrderId] => 16
)
[2] => Array
(
[eduHisRowId] => 5
[repOrderId] => 17
)
[3] => Array
(
[eduHisRowId] => 6
[repOrderId] => 18
)
[4] => Array
(
[eduHisRowId] => 7
[repOrderId] => 19
)
[5] => Array
(
[eduHisRowId] => 7
[repOrderId] => 20
)
[6] => Array
(
[eduHisRowId] => 8
[repOrderId] => 21
)
)
Now i want sort out these repeated values such that i could be able to check that the record present on index '[1] => Array' is associated with the record which is present on index '[2] => Array' & this associated relation will also be in array format like:
Array
(
[0] => Array
(
[0] => 4
[1] => Array
(
[0] => 15
)
)
[1] => Array
(
[0] => 15
[1] => Array
(
[0] => 16
[0] => 17
)
)
[2] => Array
(
[0] => 6
[1] => Array
(
[0] => 18
)
)
[3] => Array
(
[0] => 7
[1] => Array
(
[0] => 19
[0] => 20
)
)
[4] => Array
(
[0] => 8
[1] => Array
(
[0] => 21
)
)
)
where 0th index of innre mos array will contain 'eduHisRowId' value & the array on 1st index will contain 'repOrderId' values.
Thanks in advance...

Answer 1

Can I suggest a different solution? What about an array structure that looks like:
Array
(
[4] => Array
(
[0] => 15
)
[5] => Array
(
[0] => 16
[1] => 17
)
)
The keys are the eduHisRowId values and the value is an array of corresponding repOrderId values.
Creating this array would go like follows:
function consolidate($item, $key, $array) {
$rowId = $item['eduHisRowId'];
if(!array_key_exists($rowId, $array)) {
$array[$rowId] = array();
}
$array[$rowId][] = $item['repOrderId'];
}
$result = array();
array_walk($dataArray, 'consolidate', &$result);
$dataArray is your multidimensional array, the resulting array is in $result.
Reference: array_walk(), array_key_exists()