Get column values from an associative array in php - php

Question

I have an array of form:
$records = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
),
array(
'id' => 5342,
'first_name' => 'Jane',
'last_name' => 'Jones',
),
array(
'id' => 5623,
'first_name' => 'Peter',
'last_name' => 'Doe',
)
);
I want output like this :
EDIT:
Array
( array('first_Name' => John),
array('first_Name'=> Sally),
array('first_Name'=> Jane),
array('first_Name'=> Peter)
);
Can this be achieved??

Answer 1

You cannot do this since you can't have duplicate keys in an array.
Here is a related question: How to allow duplicate keys in a PHP array?
This article explains how PHP stores array internally: http://nikic.github.io/2012/03/28/Understanding-PHPs-internal-array-implementation.html.
Answer after your edit:
$arr = array();
foreach($records as $value) {
$arr[] = array('first_name' => $value['first_name']);
}
print_r($arr);

Answer 2

You can achieve your (edited) question like this:
$new_array = array();
foreach($records as $record)
$new_array[] = array('first_Name'=>$records['first_name']);

Answer 3

try this
$records = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
),
array(
'id' => 5342,
'first_name' => 'Jane',
'last_name' => 'Jones',
),
array(
'id' => 5623,
'first_name' => 'Peter',
'last_name' => 'Doe',
)
);
$tmp = array('first_name' => '');
foreach ($records as &$record) {
$record = array_intersect_key($record, $tmp);
// or $record = array('first_name' => $record['first_name']);
}
unset($record);
var_dump($records);

Answer 4

If you want to array with in the array means, surely it will generated with index key, like this
Array
( '0' => array('first_Name' => John),
'1' => array('first_Name'=> Sally),
'2' => array('first_Name'=> Jane),
'3' => array('first_Name'=> Peter)
);
Try this one,
foreach($records as $record) {
$name_array[] = Array('first_Name' =>$record['first_name']);
}
print_r($name_array);
Your output will be,
Array
(
[0] => Array
(
[first_Name] => John
)
[1] => Array
(
[first_Name] => Sally
)
[2] => Array
(
[first_Name] => Jane
)
[3] => Array
(
[first_Name] => Peter
)
)

Answer 5

To get your desired output you can use array_map, though you can get similar output with array_column which is new in PHP 5.5.
With array_map (http://3v4l.org/v8Y8Z):
<?php
$firstNames = array_map(function($record) {
return ['first_name' => $record['first_name']];
}, $records);
With array_column (http://3v4l.org/ohnGu):
$firstNames = array_column($records, 'first_name');
Note: array_column doesn't make subarrays with the first_name key.

Answer 6

you can try this one
$arr_output = array();
foreach($records as $key=>$arr)
{
$arr_output['id'][] = $arr['id'];
$arr_output['first_name'][] = $arr['first_name'];
$arr_output['last_name'][] = $arr['last_name'];
}
print_r($arr_output['first_name']); // display all first names
print_r($arr_output); // display complete output array.
Output :
Array
(
[id] => Array
(
[0] => 2135
[1] => 3245
[2] => 5342
[3] => 5623
)
[first_name] => Array
(
[0] => John
[1] => Sally
[2] => Jane
[3] => Peter
)
[last_name] => Array
(
[0] => Doe
[1] => Smith
[2] => Jones
[3] => Doe
)
)
Demo

Answer 7

This is not possible, because you cannot have multiple elements of the same key in an associative array.