Looking for a safe and efficient way to "carry" data from page to page

[amykhar]

Is there a way for me to "carry" a chunk of information around from one screen to another without using cookies?

For example, let's say I have a table that has a questions for a survey I want people to take. If I want the people to answer the questions one at a time and not all on the same page with a single click, can I query the database once and get all the questions and then use that info to show the first question, get a response, show the second question, etc.?

What I am trying to avoid is having to query for the first question, get the response, query for the second question, etc.

Amy

[Marco van Herwaarden]

You could put all in an array and post that in a hidden field. Security on this would be a different mather.

[Guy G]

Is there a way for me to "carry" a chunk of information around from one screen to another without using cookies?

For example, let's say I have a table that has a questions for a survey I want people to take. If I want the people to answer the questions one at a time and not all on the same page with a single click, can I query the database once and get all the questions and then use that info to show the first question, get a response, show the second question, etc.?

What I am trying to avoid is having to query for the first question, get the response, query for the second question, etc.

Amy
instead of carrying the info you could just have it on one page and switch everytime for each question...

like
question.php?ask=question1
question.php?ask=question2
question.php?ask=question3
...

or im wrong :/

[Andreas]

You could extend the session table.

[sabret00the]

couldn't you serialize the data to scramble it? and then carry it all in a hidden form field?

i.e.

$oldanswers = unserialize($answers);
$newanswers = $_POST['answers'];
$newanswers .= $oldanswers;
$answers = serialize($newanswers);



<input type="hidden" name="questions" value="$answers" />

i probably mean something that's not serliaze but you get what i mean, granted i have no experience of this, but the idea works.

[Andreas]

No matter if you carry the data by hidden fields, cookies or within the URL:
It can be modified by the user.
To prevent this you would have to hash the data with some secret to make sure it has not been modified.

[Xenon]

Personally i think Kirby's way is the best

add a field to the sessions table and there put in the serialized data of the already answered question.

[Dean C]

Hmm sessions are ideal for carrying answers to survey questions across pages. The only other way I'd do it is serializing the $_POST info as sabe pointed out :) But if people want to cheat they can cheat. It's a sacrifice you have to make

[amykhar]

Thanks for all the ideas, guys.

[amykhar]

Efficiency question: What would use more server resources - doing a query for each question, or doing a file read for each question? In general, are file reads more intensive than querying the database?

Amy

[Tekton]

In general, I thought that filereads were faster, right?

[Brad]

Efficiency question: What would use more server resources - doing a query for each question, or doing a file read for each question? In general, are file reads more intensive than querying the database?

Amy
It depends on what sort of table you query. If the data is temp store it in memory and destory it once you are finished with it (or put it on the hard disk).

Reading from memory will be quicker then any sort of read on the HDD

[Dean C]

Amy I think you're worrying too much about the query-side of things. Whilst as programmers we strive to make our sites as efficient as possible simple select queries even with joins, aren't that resource intensive. You can optimize them further by adding indexes as well. Anyways, database retrieval is far faster than retrieving from a file :)

[Xenon]

DB systems are more optimized that file searches, so i'd always use DB instead of files.

but of course, depending on your loadbalance, a file can sometimes be more usefull ;)

[amykhar]

Thanks, Dean :)

I'm really working right now on improving the efficiency and security of my php coding. I'm trying to learn as much as possible to make some bigger things I'm working on better.