How to code to add a record if there is none, else edit the record?

I'm slowly learning php, and I have had a lot of help from this forum so far. Thanks!

Anyway I have code below that edits a record. I had a 2 day nightmare with syntax errors on my last project, that i'm frazzled to start changing this code. Basically I want the code to check the table for a record for the username, and if there is no record then add the record, else if it finds the record to edit it.

<?php

extract($_POST);
extract($_GET);

    $april_fools = $_POST['april_fools'];
    $boss_day = $_POST['boss_day'];
    $boxing_day = $_POST['boxing_day'];
    $canada_day = $_POST['canada_day'];
    $chinese_new_year = $_POST['chinese_new_year'];
    $christmas = $_POST['christmas'];

    
 
  $query = "UPDATE holiday_reminders SET april_fools='".$april_fools."',boss_day='".$boss_day."',boxing_day='".$boxing_day."',canada_day='".$canada_day."',chinese_new_year='".$chinese_new_year."',christmas='".$christmas."' WHERE usrname='$my->username'";
  mysql_query($query);

 
 Header("Location: my-reminders.php"); 
  exit; 
?>

Code (markup):

 

Here a quick example.

$query = "UPDATE holiday_reminders SET april_fools='".$april_fools."',boss_day='".$boss_day."',boxing_day='".$boxing_day."',canada_day='".$canada_day."',chinese_new_year='".$chinese_new_year."',christmas='".$christmas."' WHERE usrname='$my->username'";
mysql_query($query);

if (!mysql_affected_rows())
{
     $query = "INSERT INTO table (fields) VALUES (values)";
     mysql_query($query) OR die( mysql_error() );
}

PHP:

 

Thank you - that gives me a good example to start with!

 

I'm close, but this error gives me no information. The new code is below.

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ',,,,1)' at line 1
(this error is given when I select to add the christmas (last) option)

$query = "UPDATE holiday_reminders SET april_fools='".$april_fools."',boss_day='".$boss_day."',boxing_day='".$boxing_day."',canada_day='".$canada_day."',chinese_new_year='".$chinese_new_year."',christmas='".$christmas."' WHERE usrname='$my->username'";mysql_query($query);
if (!mysql_affected_rows()){     $query = "INSERT INTO holiday_reminders (usrname,april_fools,boss_day,boxing_day,canada_day,chinese_new_year,christmas) VALUES ($my->username,$april_fools,$boss_day,$boxing_day,$canada_day,$chinese_new_year,$christmas)";     mysql_query($query) OR die( mysql_error() );}

Code (markup):

 

hmm, I thought maybe because the database fields had a "Not Null" attribute to it, and I wasn't passing something in every field, that was the issue. Nope...

 

forget it, I think I found it. The error is coming from somewhere else. I won't have a chance to look at it until Moday now anyway. Thanks for all the help!