We have prepared 150x3 sub-question survey on the server. When we try to fill-out the survey, the session is end. I have to log in again. With the limited numer of sub-questions (like 60x3) it works well.

What we have done:
1. Changed the "max_input_time" parameter in PHP.ini from 1000 to 4000
2. Changed "memory_limit" from 128M to 256M
3. Changed "config-defaults.php" from 128M to 256M

What we consider to do:
4. Change the max sp recursion depth 100

Any thoughts are welcome.

I guess you have some more questions than just those 150 questions with 3 subquestions, right? Because 150x3 would be 450 columns, which should be no problem for the database. Problems usually start at around 1000 columns.

The problem reveals even with 1 question and 150 subquestions.

rugams wrote: The problem reveals even with 1 question and 150 subquestions.

I apologize. W have checked it again and 1 question with 150 subquestions seems to work fine (we've cleared the cache in the meantime). The problem with loosing session starts with 2 (sic!) questions (and more) and 150 subquestions.

OK, so it is most probably not a database limit, but rather some kind of session problem. Is there any limit for the session file size in your installation? I know that LS generates quite big session files.

If your question type is array texts with many subquestions, you will get a very large database row size. This may well be your problem. Happened to me too...
Cheers, Frank

Good catch, fvanderstarre.

Yes, if this is an array text or array number, then you not only have to multiply the number of questions and the number of subquestions in each question, but also the number of answer options for each subquestion.

Let's assume that each subquestion has 5 answer options, then you have 150x3x5 and this would mean a total of 2250 columns for these questions are necessary and you are easily over the limit for the database engines.

If this is the case, then there isn't much you can do:
- create various surveys and connect them (with all the disadvantages)
- use another survey tool that has higher limits for this type of questions
- support the Feature request to allow bigger surveys (either by joining database tables, change the whole database structure, etc.). I unfortunately don't have a link to this feature request now.

fvanderstarre wrote: If your question type is array texts with many subquestions, you will get a very large database row size. This may well be your problem. Happened to me too...
Cheers, Frank

What happened to you? Loosing the session when having question types with many subquestions?

The threadstarter stated

I have to log in again

. What is meant by login? Just entering the URL or login on the backend.

The issue could be totally unrelated to the database itself. Could be e.g. Suhosin activated on the server.
www.limesurvey.org/manual/Troubleshootin...ssion_has_expired.22

What database is used?

Hi all, I am working with rugams on this survey.

After many tests we have following observations related to the topic issue:
1. The sub questions are within Multi choice (check buttons) or Multi number/text filed types - so there is just one column for answers.
2. The amount of sub questions in single question is over 150.
3. It works ok, when we have 60 sub-questions in each of three questions.

Misbahavior is as follows:
When we reach the "big" question looks like the survey is loosing the context.
When we want to move to the next question it just refreshes the current page (this with 150 sub-questions).
When we want to do any of the tasks in admin view - we need to relogin.

The same survey works well on limesurvey hosted service.

Thank you for any clues!

Regards,
M.

matos wrote: When we want to move to the next question it just refreshes the current page (this with 150 sub-questions).When we want to do any of the tasks in admin view - we need to relogin.

Please do the following check:

1.) Activate the survey.
2.) Open a different browser or a anonymous browser window (so that a different session context is used)
3.) Do the survey in that new browser/browser window
Any issues with the survey?
Still logged in LimeSurvey in the other browser/browser window.

It works the same in a new browser. I followed your instruction carefuly.
I had also tried to run it on my friends computer, who had never open the limesurvey.
Same behavior.

I think it is something with environment - as the same survey works on hosting service well.

BR,
M.

matos wrote: I think it is something with environment - as the same survey works on hosting service well.

So you can activate the survey without issues?

The hosting environment is still unknown to us. Even the Limesurvey version/build used in unknown.
As I stated be before it could be a suhosin protection on php level that's preventing running the survey.
Always difficult to diagnose via forum.