php脚本从sql表中检索枚举值

I posted the below on stackexchange for code review. But I just realized that what I am asking could be a legit question for SO. Please let me know if you think otherwise.

I have an sql table with multiple fields and 4 of them are enums. I wrote a script that runs thought the table and retrieve the enums and put them in a 2 dimension array.

Unfortunately this script is extreamly slow and I can't fix it.

<?php

require_once('mySQL_Connect.php');

$con = ConnectToDataBase();
if ($con == false)
{
    //data returned will be null
    exit;
}

$db = 'courses_db';
$table = 'courses';

$fields = array(
'training_field',
'speciality_field',
'type',
'language');

$enums = array();

foreach ($fields as $colomn) {
$sq1 = "SELECT 
            column_type 
        FROM 
            information_schema.columns 
        WHERE 
            table_schema = '$db' 
        AND 
            table_name = '$table'
        AND 
            column_name = '$colomn'";
$query =  mysqli_query($con,$sq1);

$stack = array();   
$i = 0;
$stack[$i]=$colomn;
if ($fetch = mysqli_fetch_assoc($query) )
{
    $enum = $fetch['column_type'];
    $off = strpos($enum,"(");
    $enum = substr($enum, $off+1, strlen($enum)-$off-2);
    $values = explode(",",$enum);

    // For each value in the array, remove the leading and trailing
    // single quotes, convert two single quotes to one. Put the result
    // back in the array in the same form as CodeCharge needs.

    for( $n = 0; $n < Count($values); $n++) {
    $val = substr( $values[$n], 1,strlen($values[$n])-2);
    $val = str_replace("''","'",$val);
    $stack[$i+1]=$val;
    $i++;
    }
}
    // return the values array to the caller
    //echo json_encode( $stack);
    array_push($enums,$stack);
    reset($stack);
}
echo json_encode($enums);
?> 

I finally found a solution and here it is (Hope this will be useful for someone):

function get_enum_values($connection, $table, $field )
{

    $query = " SHOW COLUMNS FROM `$table` LIKE '$field' ";
    $result = mysqli_query($connection, $query );
    $row = mysqli_fetch_array($result , MYSQL_NUM );
    #extract the values
    #the values are enclosed in single quotes
    #and separated by commas
    $regex = "/'(.*?)'/";
    preg_match_all( $regex , $row[1], $enum_array );
    $enum_fields = $enum_array[1];

    return( $enum_fields );
}

So basically there's no need to go through information_schema!

Credit goes to this blog:

http://akinas.com/pages/en/blog/mysql_enum/

As CodeCharge was mentioned in original question, there is an example in CCS online help under Utilize MySQL Enum Field Type. Sample code is similar to above, but also available in several languages.