Array Restructuring - php

Question

I have the following query result:
Array
(
[0] => stdClass Object
(
[TreatmentLog_ID] => 131
[DateAdministered] => 2016-07-15
[Notes] =>
[Treatment_ID] => 144
[AmountAdministered] => 1.5
[Injectable_ID] => 2
[InjectableName] => Baytril
)
[1] => stdClass Object
(
[TreatmentLog_ID] => 133
[DateAdministered] => 2016-07-12
[Notes] =>
[Treatment_ID] => 146
[AmountAdministered] => 1.2
[Injectable_ID] => 20
[InjectableName] => Vitamin C
)
[2] => stdClass Object
(
[TreatmentLog_ID] => 133
[DateAdministered] => 2016-07-12
[Notes] =>
[Treatment_ID] => 147
[AmountAdministered] => 1.3
[Injectable_ID] => 21
[InjectableName] => Vitamin E
)
)
I'd like to be able to restructure the array into something like this:
Array
(
[0] => stdClass Object
(
[TreatmentLog_ID] => 131
[DateAdministered] => 2016-07-15
[Notes] =>
[Treatments] => Array
(
[0] => stdClass Object
(
[Treatment_ID] => 144
[AmountAdministered] => 1.5
[Injectable_ID] => 2
[InjectableName] => Baytril
)
)
)
[1] => stdClass Object
(
[TreatmentLog_ID] => 133
[DateAdministered] => 2016-07-12
[Notes] =>
[Treatments] => Array
(
[0] => stdClass Object
(
[Treatment_ID] => 146
[AmountAdministered] => 1.2
[Injectable_ID] => 20
[InjectableName] => Vitamin C
)
[1] => stdClass Object
(
[Treatment_ID] => 147
[AmountAdministered] => 1.3
[Injectable_ID] => 21
[InjectableName] => Vitamin E
)
)
)
)
Notice how the second array looks merges the InjectableName, AmountAdministered, Injectable_ID, and Treatment_ID into the array Treatments if the TreatmentLog_ID is a match. Typically working with arrays isn't a problem, but this one has me stumped. Also I cannot change the query.
How could I pull this off in PHP?

Answer 1

The solution using isset and array_values functions:
// $arr is your initial array
$result = [];
foreach ($arr as $obj) {
$innerObj = (object)[ 'Treatment_ID' => $obj->Treatment_ID, 'AmountAdministered' => $obj->AmountAdministered,
'Injectable_ID' => $obj->Injectable_ID, 'InjectableName' => $obj->InjectableName ];
if (!isset($result[$obj->TreatmentLog_ID])) {
$result[$obj->TreatmentLog_ID] = (object)[
'TreatmentLog_ID' => $obj->TreatmentLog_ID,
'DateAdministered' => $obj->DateAdministered,
'Notes' => $obj->Notes,
'Treatments' => [$innerObj]
];
} else {
$result[$obj->TreatmentLog_ID]->Treatments[] = $innerObj;
}
}
$result = array_values($result);
print_r($result); // will output the expected result

Answer 2

Try this.
We use array_filter() to fetch all of the elements from the $inputArray with the same TreatmentLog_ID. Then we transform those filtered elements with array_map(). We have to create a copy of each element with clone, since they're objects and objects are passed by reference. Then we unset() the keys we don't need in the copy.
<?php
$inputArray = [
0 => (object) [
'TreatmentLog_ID' => 131,
'DateAdministered' => '2016-07-15',
'Notes' => '',
'Treatment_ID' => 144,
'AmountAdministered' => 1.5,
'Injectable_ID' => 2,
'InjectableName' => 'Baytril'
],
1 => (object) [
'TreatmentLog_ID' => 133,
'DateAdministered' => '2016-07-12',
'Notes' => '',
'Treatment_ID' => 146,
'AmountAdministered' => 1.2,
'Injectable_ID' => 20,
'InjectableName' => 'Vitamin C'
],
2 => (object) [
'TreatmentLog_ID' => 133,
'DateAdministered' => '2016-07-12',
'Notes' => '',
'Treatment_ID' => 147,
'AmountAdministered' => 1.3,
'Injectable_ID' => 21,
'InjectableName' => 'Vitamin E'
],
];
$transformedArray = [];
foreach ($inputArray as $key => $value)
{
$transformedArray[$key] = [
'TreatmentLog_ID' => $value->TreatmentLog_ID,
'DateAdministered' => $value->DateAdministered,
'Notes' => $value->Notes,
'Treatments' => array_map(
function ($v) {
$copy = clone $v;
unset($copy->Notes);
unset($copy->DateAdministered);
unset($copy->TreatmentLog_ID);
return $copy;
},
array_filter($inputArray, function ($v) use ($value) {
return $v->TreatmentLog_ID == $value->TreatmentLog_ID;
})
)
];
}
var_dump($transformedArray);
This gives me:
array(3) {
[0]=>
array(4) {
["TreatmentLog_ID"]=>
int(131)
["DateAdministered"]=>
string(10) "2016-07-15"
["Notes"]=>
string(0) ""
["Treatments"]=>
array(1) {
[0]=>
object(stdClass)#5 (4) {
["Treatment_ID"]=>
int(144)
["AmountAdministered"]=>
float(1.5)
["Injectable_ID"]=>
int(2)
["InjectableName"]=>
string(7) "Baytril"
}
}
}
[1]=>
array(4) {
["TreatmentLog_ID"]=>
int(133)
["DateAdministered"]=>
string(10) "2016-07-12"
["Notes"]=>
string(0) ""
["Treatments"]=>
array(2) {
[1]=>
object(stdClass)#6 (4) {
["Treatment_ID"]=>
int(146)
["AmountAdministered"]=>
float(1.2)
["Injectable_ID"]=>
int(20)
["InjectableName"]=>
string(9) "Vitamin C"
}
[2]=>
object(stdClass)#7 (4) {
["Treatment_ID"]=>
int(147)
["AmountAdministered"]=>
float(1.3)
["Injectable_ID"]=>
int(21)
["InjectableName"]=>
string(9) "Vitamin E"
}
}
}
[2]=>
array(4) {
["TreatmentLog_ID"]=>
int(133)
["DateAdministered"]=>
string(10) "2016-07-12"
["Notes"]=>
string(0) ""
["Treatments"]=>
array(2) {
[1]=>
object(stdClass)#8 (4) {
["Treatment_ID"]=>
int(146)
["AmountAdministered"]=>
float(1.2)
["Injectable_ID"]=>
int(20)
["InjectableName"]=>
string(9) "Vitamin C"
}
[2]=>
object(stdClass)#9 (4) {
["Treatment_ID"]=>
int(147)
["AmountAdministered"]=>
float(1.3)
["Injectable_ID"]=>
int(21)
["InjectableName"]=>
string(9) "Vitamin E"
}
}
}
}
Let's break down how we build Treatments:
'Treatments' => array_map(
function ($v) {
$copy = clone $v;
unset($copy->Notes);
unset($copy->DateAdministered);
unset($copy->TreatmentLog_ID);
return $copy;
},
array_filter($inputArray, function ($v) use ($value) {
return $v->TreatmentLog_ID == $value->TreatmentLog_ID;
})
)