Remove Child Array If Value of A Key is Duplicate - php

Question

I want to remove a child array from a multi-dimensional array in case a duplicate value found for a particular key. The answer(s) here didn't work at all. The answer here works, however, for large amount of arrays, that gets pretty slower. Looking for a cleaner and faster solution.
Example PHP Array
$args = array();
$args[] = array(
'section' => array(
'id' => 'section1',
'name' => 'Section 1',
),
'name' => 'Shortcode Name',
'action' => 'shortcodeaction',
'icon' => 'codeicon',
'image' => 'codeimage',
);
$args[] = array(
'section' => array(
'id' => 'section2',
'name' => 'Section 2',
),
'name' => 'Shortcode2 Name',
'action' => 'shortcodeaction2',
'icon' => 'codeicon2',
'image' => 'codeimage2',
);
$args[] = array(
'section' => array(
'id' => 'section3',
'name' => 'Section 3',
),
'name' => 'Shortcode3 Name',
'action' => 'shortcodeaction3',
'icon' => 'codeicon3',
'image' => 'codeimage3',
);
$args[] = array(
'section' => array(
'id' => 'section1',
'name' => 'Section 4',
),
'name' => 'Shortcode4 Name',
'action' => 'shortcodeaction4',
'icon' => 'codeicon4',
'image' => 'codeimage4',
);
$args[] = array(
'section' => array(
'id' => 'section5',
'name' => 'Section 5',
),
'name' => 'Shortcode5 Name',
'action' => 'shortcodeaction5',
'icon' => 'codeicon5',
'image' => 'codeimage5',
);
$sections = array();
foreach ( $args as $arg ) {
$sections[] = $arg['section'];
}
And, the print_r($sections) result.
Array
(
[0] => Array
(
[id] => section1
[name] => Section 1
)
[1] => Array
(
[id] => section2
[name] => Section 2
)
[2] => Array
(
[id] => section3
[name] => Section 3
)
[3] => Array
(
[id] => section1
[name] => Section 4
)
[4] => Array
(
[id] => section5
[name] => Section 5
)
)
Both Array[0] and Array[3] has the same value for the key id, therefor the entire Array[3] has to be removed in my case to avoid duplicates.
This is working for me though, but it gets really slow when there are 100s or more arrays.
$knownIds = array();
foreach( $sections AS $key=>$item ) {
if( array_key_exists($item['id'], $knownIds) === true ) {
unset( $sections[$key] );
} else {
$knownIds[$item['id']] = $key;
}
}
$sections = array_values($sections);
Tried several answers here in StackOverflow (including this), but none of them helped in my case.
Thanks

Answer 1

You can modify the whole using array_column and array_filter -
//get all the sections value
$section = array_column($args, 'section');
//store ids in temp array
$idArray = array_unique(array_column($section, 'id'));
//filter the array having unique id
$uniqueSections = array_filter($section, function ($key, $value) use ($idArray) {
return in_array($value, array_keys($idArray));
}, ARRAY_FILTER_USE_BOTH);
var_dump($uniqueSections);
For PHP <5.5
$section = array_map(function($args) {
return $args['section'];
}, $args);
$idArray = array_unique(array_map(function($section){return $section['id'];}, $section));