Query DB for set Interval to Get Specific Data

[rsmith]

All,
I have a table that stores information about an authorization that is initiated when a user inputs a pin number. What I need to do is continuously query a table until an approved or denied entry is found in the database. The approval/denial should take no longer than 10 seconds to show up in the database but in the event it takes longer I need it to keep querying. So I need to set a time out of 30 seconds but as soon as the row in the db exists with the approval or denial I need the script to go to the next portion. What's the best way to do this?

TIA!

[bretticus]

IS this "approval" the result of a payment gateway transaction? Is it external to your system? Just trying to fathom why it takes so long (30 seconds is an eternity in computer time 🙂

If it actually takes 10-30 seconds for your database to query the approval, then I suggest ramping up the script execution time on your php script. One easy trick I have seen in the past, is to show a hidden layer with a animated gif or animated flash when the user clicks the submit button. The animation can be a "progress bar" that just goes back and forth. The idea being that the user gets the reassuring gesture that the application has not become unresponsive.

If it's an external transaction and you are dependent upon a 3rd party, then you are on the right track with setInterval. That is, you could use setInterval() to continuously call a function that uses AJAX to call a php page that queries the database looking for the approval code.

Here is an example using setInterval().

However, this might be a little tricky with the ajax call mixed in. I have used Ajax.PeriodicalUpdater from the prototype javascript library in the past to do similar things. It uses setInterval() at it's core, I believe, to automatically call a remote page (your php page that queries for the existence of the approval, for example.) based on what the php page returns, you can decide to move on, etc.

Good luck!

[rsmith]

You sly boots.... </family_guy_ref>. The transaction doesn't take 30 seconds, I just need the script to run no more than 30 seconds before dumping the user back to a page that says a timeout occurred, please resubmit order. The animated gif is definitely something that is needed as well. The db storing the transaction approval is technically under another domain but is hosted on the same server so response time should be minimal. I'll look at your two links. Thanks!

[rsmith]

I looked into the setInterval article but he never says where to actually place the setInterval at and my testing hasn't even yielded his example to work. Have you used it successfully before?

[bretticus]

If I understand you right, you are running the pin against the database from a form. Unless you would like to not submit a form and submit the pin via AJAX, I suggest that you set max script time. However, the goal here, as you've stated, is to timeout gracefully.

Check out this article.