avoiding DB re-entry after page refresh

[jrmatmillerclan]

Suppose page-one.html contains a standard HTML form that collects information from the user. Clicking the Submit button on page-one.html POSTs the results over to page-two.php, which runs the appropriate PHP code to collect the results and insert them into a MySQL database. All is good.

However, if the user hits the browser refresh button, the PHP code on page-two.php is re-run, which produces a second entry in the database. This, of course, is not so good. Does anyone have suggestions on how to prevent this from happening? I've tried to keep the page from getting cached by the browser, but have been getting inconsistent results. Any wisdom would be much appreciated.

Thanks,
Jim

[pinoy]

Put a unique key in your database, in this case if the user hits the browser refresh button, the data on the first entry in the database will not be duplicated, hence the database will return a duplicate error, just workaround on how you customize this error.

Pinoy

[Tracer]

Maybe you could use

mysql_insert_id()

and an IF statement

//define a new var id if unset
if !isset($temp_id) {
$temp_id=mysql_insert_id()
}

//check to see if same
if ($temp_id==mysql_insert_id()) {
echo "ALREADY THERE";
{
ELSE

whatever

[Arenium]

unless I'm missing something, just use mysql_pconnect instead of mysql_connect 😃

pconnect is "persistent connection". so if one already exists, AFAIK, php reuses it.

[eXSeSSive]

I think the 2 easiest options are.....
A) Search the DB first for a duplicate entry as was suggested above.

😎 Sometimes the entries may be duplicate on purpose - in this case, CLEAR the variables before you set them. Thus, if the page is refreshed, no data is passed from the submission form and the variables are empty. Just check for an empty variable and return an error.

Like so...

unset($Username);
unset($Password);
$Username = $HTTP_POST_VARS["Username"];
$Password = $HTTP_POST_VARS["Password"];

if (empty($Username) || empty($Password))
{
echo "<H2> You did not enter a Username and/or Password.
";
echo "<H2> Both are required. Please try again. </H2>";

• XS