How do I remove one array from another in php? - php

Question

I have the following arrays in PHP:
print_r($employees) =
Array
(
[0] => Array
(
[p_id] => T29083999
[name] => Robert Plaxo
)
[1] => Array
(
[p_id] => T29083388
[name] => Yvan Sergei
)
[2] => Array
(
[p_id] => T21083911
[name] => Rhonda Saunders
)
[3] => Array
(
[p_id] => H02910382
[name] => Miguel Mercado
)
)
then this array:
print_r($record) =
Array
(
[0] => Array
(
[c_id] => 1
[section] => 1061
[term] => 201631
[p_id] => T29083388
[c_date] => 2016-04-01 09:14:00
)
)
I want to remove the array element from $employees that matches the p_id of $record. Array $record may have multiple entries like the one shown. If so, any p_id in $record must be removed from $employees.
I tried:
foreach ($employees as $k => $e) {
foreach ($record as $r) {
if ($e['p_id']==$r['p_id']) {
echo "found it!";
// if I uncomment the next line, it crashes! (500 server error)
// unset $employees[$k];
}
}
}
I just want to remove any element from $employees that has any employee that matches any record in $record with that employee id.

Answer 1

You were almost there; just needed parens around your unset()
I also took the liberty to change some of your variable names as single character variable names bother me.
$employees[] = [
'p_id' => 'T29083999',
'name' => 'Robert Plaxo',
];
$employees[] = [
'p_id' => 'T29083388',
'name' => 'Yvan Sergei',
];
$employees[] = [
'p_id' => 'T21083911',
'name' => 'Rhonda Saunders',
];
$employees[] = [
'p_id' => 'H02910382',
'name' => 'Miguel Mercado',
];
$records[] = [
'c_id' => '1',
'section' => '1061',
'term' => '201631',
'p_id' => 'T29083388',
'c_date' => '2016-04-01 09:14:00',
];
foreach ($employees as $key => $employee) {
foreach ($records as $record) {
if ($employee['p_id'] == $record['p_id']) {
echo "found it!";
unset($employees[$key]);
}
}
}
echo "<pre>";
print_r($employees);
Outputs
found it!
Array
(
[0] => Array
(
[p_id] => T29083999
[name] => Robert Plaxo
)
[2] => Array
(
[p_id] => T21083911
[name] => Rhonda Saunders
)
[3] => Array
(
[p_id] => H02910382
[name] => Miguel Mercado
)
)

Answer 2

The short solution using array_column and array_filter functions. It will also fit your requirement "Array $record may have multiple entries":
$p_ids = array_column($record, "p_id");
$employees = array_filter($employees, function($v) use($p_ids){
return !in_array($v["p_id"], $p_ids);
});
print_r($employees);
The output:
Array
(
[0] => Array
(
[p_id] => T29083999
[name] => Robert Plaxo
)
[2] => Array
(
[p_id] => T21083911
[name] => Rhonda Saunders
)
[3] => Array
(
[p_id] => H02910382
[name] => Miguel Mercado
)
)