Why is this happening? Urent help.

[mat-tastic]

Hey Guys,

 

I been programming php for about 3 years now. However this one has got me stumped.

 

  if (isset($_GET['vote'])) {
  // enter the votes and record ip etc etc
  
  $votes_query = "SELECT * FROM screenshots WHERE id = '$vote'";
  $votes_result = mysql_query($votes_query, $conn_abrv) or die(mysql_error());
  $id = $_GET['vote'];
  $addvotesql = "UPDATE screenshots SET votes = votes + 1 WHERE id = '$id'";
  $addvote = mysql_query($addvotesql, $conn_abrv) or die(mysql_error());
}

 

It keeps adding TWO to the database, instead of one. I have tried loads of different ways, I have tried getting the value of $votes, then adding one to it. I echo'ed the result of the addition, and it had the correct result, however then checked the database, and it had added two?

 

Please help!

 

Does anyone also know a way to effectively stop people voting twice, apart from IP bans and sessions/cookies?

[waynew]

Em... try this; although I doubt that it will change anything.

 

$addvotesql = "UPDATE screenshots SET votes = (votes + 1) WHERE id = '$id'";

 

That's a strange one.

[mat-tastic]

Nope, thanks anyway. It still added two.

 

I have made sure the query isn't being performed twice, I have checked the table structure.

 

This is so confusing.

[mat-tastic]

Any other ideas? This is weird.

[DamienRoche]

Maybe try to separate the calculation. Retrieve the previous number, add 1 and reinsert.

 

$num = $fetch['votes'] +1; ///of course, $fetch will have to be created

 

then..

 

SET votes = $num WHERE..etc

 

not ideal, but should work. Very strange.

 

[mat-tastic]

I tried that earlier, I just tried it again, it went from 10 to 12. This so weird.

[mat-tastic]

UPDATE: I just did a test, I made it remove one number from the total number of votes, and it only took one off.

 

SO it appears that its just adding. If I add one it always adds two.

[redarrow]

you havent got the database set up correctly i guess change the field to a INT

 

i bet your incrementing on the database side off things lol.......

[PFMaBiSmAd]

Your browser is requesting the page twice. This is either due to the browser (FF will request a page twice if the page does not have any character encoding specified and FF is applying its' default encoding), you have some javascript that is submitting the form and the form is being submitted by the browser as well, or you are using url rewriting and there is a problem with a trailing slash (I don't recall if a missing slash or an extra slash is at fault.)

[mat-tastic]

Your browser is requesting the page twice. This is either due to the browser (FF will request a page twice if the page does not have any character encoding specified and FF is applying its' default encoding), you have some javascript that is submitting the form and the form is being submitted by the browser as well, or you are using url rewriting and there is a problem with a trailing slash (I don't recall if a missing slash or an extra slash is at fault.)

 

Ahh, you got it, I just tried in IE, and it is fine. So how do I fix this firefox issue? Thank you so much. Any further help on the firefox issue would be great.

 

I am used to IE messing about, not firefox.

[mat-tastic]

Not sure where to start. It must be the firefox encoding issue? Not sure how to fix that.

[PFMaBiSmAd]

Make your page a valid HTML document with a doctype and a specific character encoding so that FF won't reload the page in order to apply its' own default character encoding. Here is the thread where I learned that FF does this - http://www.phpfreaks.com/forums/index.php/topic,216715.msg992061.html#msg992061

[mat-tastic]

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

 

I have set that and done a doctype. It still happens.

 

However when I manually change the encoding in firefox > view > character encoding, it reloads the page once. And just adds one to the database like it should do.

 

This is well annoying. It is definitely the page reloading, Live HTTP Headers confirms it.

[PFMaBiSmAd]

Here is a universal fix -

 

Use sessions and set a session variable that says that the form processing code has been executed once. Check your session variable on each page request and if it is already set, skip over the form processing code.

[mat-tastic]

Thanks, I will do that.