Change the order of a result in PHP WHILE from Mysql

Question

I am with the following difficulty, in a table are stored records of product categories, I made the connection mysqli, SELECT and WHILE, and everything is fine so far, but what I’m having difficulty is to leave a record of WHILE last, in case it would be the category record called "OTHERS", because the SELECT is with ORDER BY cat_nome ASC; and below "OTHERS" there are other categories with names beginning with "P", "Q", "R", "S" (...).

Summarizing the SELECT, it’s like this:

<?php
$sql_cat_cad = "SELECT 
                   `cat_id`,
                   `cat_nome`
                FROM 
                    `categoria` 
                WHERE 
                    `cat_id_pai` IS NULL
                ORDER BY 
                    `cat_nome`
                        ASC
                ";

$query_cat_cad = mysqli_query( $mysqli, $sql_cat_cad );
$conta_cat_cad = mysqli_num_rows( $query_cat_cad );
if( $conta_cat_cad > 0 ) {
    echo "<select name='categorias' id='categorias'>\n";
    echo "<option value=''>Selecione a categoria</option>\n";
    while( $cat = mysqli_fetch_array( $query_cat_cad ) ) {
        echo "<option value='" . $cat['cat_id'] . "'>" . stripslashes( $cat['cat_nome'] ) . "</option>\n";
    }
    echo "</select>\n";
}
?>

Briefly resulting in WHILE:

Adapters

Supports for Forearm

Speakers and Subwoofer

Microphones

Mouse Pads

Other

Scanners

CPU supports

USB Padlocks

I’d like to change the code so it stays that way:

Adapters

Supports for Forearm

Speakers and Subwoofer

Microphones

Mouse Pads

Scanners

CPU supports

USB Padlocks

Other

Answer 1

First you must get the cat_id relating to cat_nome "Others". This way you can make an ordering with case test:

SELECT cat_id, cat_nome FROM categoria WHERE cat_id_pai IS NULL
ORDER BY (CASE WHEN `cat_id`=<ID_QUE_ENCONTROU> THEN 1 ELSE 0 END) ASC, cat_nome ASC

Reference: https://www.w3schools.com/sql/func_mysql_case.asp

EDIT

Dynamically ordering by the term:

SELECT `cat_id`, `cat_nome` FROM `categoria` WHERE `cat_id_pai` IS NULL
ORDER BY (CASE WHEN `cat_nome`="Outros" THEN 1 ELSE 0 END) ASC, `cat_nome` ASC