为每个MySQL行调用一个函数

Question

I have a standard MySQL database, with around 60 rows (as in user accounts). When I first made it I made the mistake of making session IDs the same as the simple account ID, now I want to fix my mistake and I am obviously not going to go through 60 rows to reset them different secure session IDs, so I am writing this function:

function generate_sessionid(){
    return bin2hex(openssl_random_pseudo_bytes(32));
}

function assign_all_sessionids(){
    $sessionid = generate_sessionid();

    $conn = sql_connect();
    $result = mysqli_query($conn, "UPDATE accounts SET sessionid='$sessionid' WHERE 1");
    sql_disconnect($conn);
}
assign_all_sessionids();

Problem: Every account in the database gets the same random session ID as the rest. How do I make it recall the function for each row in order to allow it to be random for each row?

Answer 1

Try get user's count from DB and simply execute it N times

function assign_all_sessionids(){

  $conn = sql_connect();

  // getting users count
  // here just change 'id' to your id parameter
  $result = mysqli_query($conn, "SELECT id FROM accounts"); 
  $arr = $result->fetch_array(MYSQLI_NUM);

  // executing N times
  for($i = 0; $i < $result->num_rows; $i++){
     $sessionid = generate_sessionid();
  // here just change 'id' to your id parameter again
     mysqli_query($conn, "UPDATE accounts SET sessionid='$sessionid' WHERE `id`=".$arr[$i]);
  }

sql_disconnect($conn);
}