Question

I am deleting a row (user) from the table Accounts and I am trying to set the values “Following Count” and “Follower Count” to their value with one subtracted. But for some reason that does not happen. The account deletes successfully, but the decrement doesn’t happen.

Please can you tell me what I am doing wrong:

$query = mysql_query("SELECT * FROM `Accounts` WHERE `Username` = '$username' AND `Password` = '$password' AND `Email Address` = '$emailAdd'");
    if (mysql_num_rows($query) < 1) {
        exit("Account doesn't exist");
    }
    $row = mysql_fetch_assoc($query);
    $id = $row["id"];
    $query = NULL;
    mysql_query("DELETE FROM `Comments` WHERE `accountID` = '$id'");
    mysql_query("DELETE FROM `Likes` WHERE `accountID` = '$id'");
    mysql_query("DELETE FROM `Posts` WHERE `accountID` = '$id'");
    mysql_query("DELETE FROM `Accounts` WHERE `id` = '$id'");
    $arg = mysql_query("SELECT * FROM Following WHERE followingUserID = '$id'");
    if (mysql_num_rows($arg) >= 1) {
        for ($i = 0; $i < mysql_num_rows($arg); $i++) {
            $arr = mysql_fetch_assoc($arg);
            $followingUserID = $arr['followingUserID'];
            $followedUserID = $arr['followedUserID'];
            $art = mysql_fetch_assoc(mysql_query("SELECT `Following Count` FROM Accounts WHERE `id` = '$followedUserID'"));
            $followingCount = $art['Following Count'];
            $followingCount = $followingCount-1;
            $arts = mysql_fetch_assoc(mysql_query("SELECT `Follower Count` FROM Accounts WHERE `id` = '$followingUserID'"));
            $followedCount = $arts['Followed Count'];
            $followedCount = $followedCount-1;
            mysql_query("UPDATE Accounts SET `Following Count` = '$followingCount' WHERE `id` = '$followingUserID'");
            mysql_query("UPDATE Accounts SET `Follower Count` = '$followedCount' WHERE `id` = '$followedUserID'");
            mysql_query("DELETE FROM Following WHERE followingUserID = '$id'");
        }
    }

    exit("Closed");

Answer 1

Why not simply do

 mysql_query("UPDATE Accounts SET `Following Count` = (`Following Count` - 1) WHERE `id` = '$followingUserID'");

 mysql_query("UPDATE Accounts SET `Follower Count` = (`Following Count` - 1) WHERE `id` = '$followedUserID'");

this way you wont need the 2 selects.