Question

I have a situation with a MySQL query like this:

• Category1 – Item 1
• Category1 – Item 2
• Category1 – Item 3
• Category2 – Item 3
• Category2 – Item 4
• Category2 – Item 5
• Category2 – Item 1
• Category3 – Item 4
• Category3 – Item 10
• Category X – Item X or Item(1,2,3…. existing)

How can I group by category in PHP?

Database scheme:

MySQL query:

$query = "SELECT cat.category_name, ch.channel_name 
FROM `type_categ` tc , `categories` cat , `channels` ch
WHERE cat.category_id = tc.category_id AND ch.channel_id = tc.channel_id
ORDER BY cat.category_name ASC"

Output:

var_dump($category)
array(x) { 
    [0]=> array(2) { 
            ["category_name"]=> string(8) "Category1" 
                ["channel_name"]=> string(15) "Item1" 
            } 
    [1]=> array(2) { 
            ["category_name"]=> string(8) "Category1" 
                ["channel_name"]=> string(17) "Item2" 
            } 
    [2]=> array(2) { 
            ["category_name"]=> string(8) "Category1" 
                ["channel_name"]=> string(10) "Otem 5" 
            } 
                  ... ...
    [x]=> array(2) { 
            ["category_name"]=> string(8) "Category x" 
                ["channel_name"]=> string(10) "Item x" 
            } 

} 

Answer 1

You could just iterate over the data creating the array in the format you want.

Something like this maybe (working examle here);

<?php
$raw_data = array(
   array('category_name' => 'Category1', 'channel_name' => 'Item 1'),
   array('category_name' => 'Category3', 'channel_name' => 'Item 2'),
   array('category_name' => 'Category1', 'channel_name' => 'Item 2'),
   array('category_name' => 'Category3', 'channel_name' => 'Item 1'),
   array('category_name' => 'Category2', 'channel_name' => 'Item 2'),
   array('category_name' => 'Category2', 'channel_name' => 'Item 1')
);

$sorted = array();

foreach ($raw_data as $k => $v) {
   if(!array_key_exists($v['category_name'], $sorted )) {
      $sorted[$v['category_name']] = array();
   }
   $sorted[$v['category_name']][] = $v['channel_name'];
   sort($sorted[$v['category_name']]);
}
ksort($sorted);
print_r($sorted);
?>