Question

In this code I think maybe it would be best to close after both the if and else but it seems off to close it twice.

<?php 
$member_id = "";
require("connect.php");
if (isset($_POST['member_id']))$member_id = fix_string($_POST['member_id']);

$sql=("DELETE FROM members WHERE member_id = '$member_id'");
$res = mysqli_query($con, $sql);

if (mysqli_affected_rows($con) == 1) {
    echo "member with ID of ".$member_id." has been removed from members table";
} else {
    echo "member was not deleted";
}

function fix_string($string) {
    if (get_magic_quotes_gpc()) $string = stripslashes($string);
    return htmlentities ($string);
}
?>

Answer 1

It is very common practice to open the db connection at the beginning, and close your connection once at the end. You don’t need to do it in the middle of your code.

Closing database connections isn’t absolutely required, as seen in the PHP manual page for mysql_close(), but it is considered good practice by many to do so.

There is a rare exception to this. If your program is going to be doing some heavy processing for several minutes, you might want to close the db connection before this. If you need it again after the processing, open the db connection again. The reason for this is that the MySQL connection will eventually time out, and then it may lead to more problems in your program.