Array sorting based on the string given

Question

I have a php array coming as result set from database.

as i am less familiar with mySQL sorting, i want to sort my result set based on the a particular string say "madhapur"

$arr=array(    
    array("name" => 'madhapur',"population" =>'1000'),
    array("name" => 'jubiliee hills',"population" =>'800'),
    array("name" => 'madhapur',"population" =>'900'),
    array("name" => 'adikmet',"population" =>'200'),
    array("name" => 'sr nagar',"population" =>'3000'),
    array("name" => 'jubilee hills',"population" =>'1200'),
    array("name" => 'madhapur',"population" =>'1000')   
    );

I am expecting the result as below

$arr=array(
array("name" => 'madhapur',"population" =>'1000'),
array("name" => 'madhapur',"population" =>'1000'),
array("name" => 'madhapur',"population" =>'900'),
array("name" => 'adikmet',"population" =>'200'),
array("name" => 'jubilee hills',"population" =>'1200'),
array("name" => 'jubiliee hills',"population" =>'800'),
array("name" => 'sr nagar',"population" =>'3000'),
);

I tried using usort but all of them are used to sort either descending or ascending.

function sortByName($a,$b){
         return $b['name'] - $a['name'];
    }
usort($arr,'sortByName');

So the only constraint is, arrays with `name` as `madhapur` should come at the beginning, right? — Rajdeep Paul, Jan 12 '16 at 13:35
to sort using mySQL i need to write stored procedure unless i can't pass name as parameter. — saikiran, Jan 12 '16 at 14:17

score 2 · Answer 1 · answered Jan 12 '16 at 13:52

First order by name and population in your sql, as your example appears to show everything ordered in that manner apart from the specific name (madhapur) promoted to the top

(note DB class is an example because i dont know what db access methods you use):

$arr = DB::Query("SELECT name, population 
                  FROM tablename 
                  ORDER BY name ASC, population DESC");

then you can iterate the array, and place the elements with the name you want at the beginning:

function nameAtFront($arr, $name){

    $copy = $arr;
    $total = count($arr);
    while($total--){
        if($copy[$total]['name']==$name){
            unset($arr[$total]);
            array_unshift($arr, $copy[$total]);
        }
    }
    return $arr;
}
$out = nameAtFront($arr, 'madhapur');
var_dump($out);

You could do this directly in SQL as well, which would probably be the best option: http://stackoverflow.com/questions/14104055/ordering-by-specific-field-value-first — Steve, Jan 12 '16 at 14:05
I know this but for this i need to write stored procedure to pass name as parameter. i don't want that. — saikiran, Jan 12 '16 at 14:16

score 1 · Accepted Answer · answered Jan 12 '16 at 13:44

1

To sort the name madhapur to the top and otherwise leave the order of elements as is/random:

usort($arr, function (array $a, array $b) {
    $a = $a['name'] == 'madhapur';
    $b = $b['name'] == 'madhapur';

    if ($a == $b || (!$a && !$b)) {  // both equal or both not madhapur
        return 0;
    } else if ($a) {
        return -1;
    } else {
        return 1;
    }
});

But this is really something that should be done in SQL.

answered Jan 12 '16 at 13:44

deceze

510,633
85
743
889

i am wondering how to pass that madhapur to anonymous function in the usort. it is not static. – saikiran Jan 12 '16 at 13:47
`function (..) use ($name) { .. }`, where `$name` is a variable in the current scope which holds 'madhapur'. – deceze Jan 12 '16 at 13:47

score 0 · Answer 3 · answered Jan 12 '16 at 13:58

0

I hope this will help you

function aasort (&$array, $key) {
$sorter=array();
$ret=array();
reset($array);
foreach ($array as $ii => $va) {
    $sorter[$ii]=$va[$key];
}
asort($sorter);
foreach ($sorter as $ii => $va) {
    $ret[$ii]=$array[$ii];
}
$array=$ret;
}

for more detail take reference from Sort Multi-dimensional Array by Value

answered Jan 12 '16 at 13:58

Shailesh Singh

317
1
11

Reference link http://stackoverflow.com/questions/2699086/sort-multi-dimensional-array-by-value – Shailesh Singh Jan 12 '16 at 14:00

Array sorting based on the string given

3 Answers3