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<!--T:1-->
__TOC__
__TOC__


=Getting started=
=Getting started= <!--T:2-->


<!--T:3-->
If you don't want to read half the manual to get a feeling what can be done with Limesurvey we recommend to watch some videos (see below).
If you don't want to read half the manual to get a feeling what can be done with Limesurvey we recommend to watch some videos (see below).


<!--T:4-->
After that the [[Creating surveys - Introduction]] manual page might be a good start.
After that the [[Creating surveys - Introduction]] manual page might be a good start.


==I need a quick introduction for LimeSurvey==
==I need a quick introduction for LimeSurvey== <!--T:5-->


<!--T:6-->
For a first start have a look at our very basic [[LimeSurvey Video-Tutorial]].
For a first start have a look at our very basic [[LimeSurvey Video-Tutorial]].


<!--T:7-->
There is [http://vimeo.com/4951738 another tutorial] which shows you how to get started with using Lime Survey to conduct online surveys. In [http://vimeo.com/4951738 this video] we'll create our first survey, deliver it to a user and then view the submitted results.
There is [http://vimeo.com/4951738 another tutorial] which shows you how to get started with using Lime Survey to conduct online surveys. In [http://vimeo.com/4951738 this video] we'll create our first survey, deliver it to a user and then view the submitted results.


<!--T:8-->
There are some '''more videos on YouTube''':
There are some '''more videos on YouTube''':


<!--T:9-->
'''''Limesurvey:'''''
'''''Limesurvey:'''''
*[http://www.youtube.com/watch?v=96WdtqDmRVw Planning a survey]
*[http://www.youtube.com/watch?v=96WdtqDmRVw Planning a survey]
Line 24: Line 31:
*[http://www.youtube.com/watch?v=5fI9Fyk5UCk Exporting data from LimeSurvey]
*[http://www.youtube.com/watch?v=5fI9Fyk5UCk Exporting data from LimeSurvey]


<!--T:10-->
'''''Old PHP-surveyor videos:'''''
'''''Old PHP-surveyor videos:'''''
*[http://www.youtube.com/watch?v=c8OiA0bv8Rk Getting to the phpsurveyors Admin Pages]
*[http://www.youtube.com/watch?v=c8OiA0bv8Rk Getting to the phpsurveyors Admin Pages]
Line 32: Line 40:
*[http://www.youtube.com/watch?v=NcnK5YsfB8g Emailing to the respondents]
*[http://www.youtube.com/watch?v=NcnK5YsfB8g Emailing to the respondents]


=Survey design and layout=
=Survey design and layout= <!--T:11-->


==How do I get rid of the <span style='color:red'>*</span> (red asterisk) of mandatory questions?==
==How do I get rid of the <span style='color:red'>*</span> (red asterisk) of mandatory questions?== <!--T:12-->


<!--T:13-->
In '''LimeSurvey Version 1.80 and above''' the red asterisk of mandatory questions is set within the template.css file ("asterisk" class). To hide it:
In '''LimeSurvey Version 1.80 and above''' the red asterisk of mandatory questions is set within the template.css file ("asterisk" class). To hide it:
*Open the template editor
*Open the template editor
Line 44: Line 53:
*Clear your browser cache so that the edited template.css is reloaded and not taken from cache.
*Clear your browser cache so that the edited template.css is reloaded and not taken from cache.


<!--T:14-->
In '''LimeSurvey Version 1.53''' the red asterisk of mandatory questions is set within the css "asterisk" class. To hide it:
In '''LimeSurvey Version 1.53''' the red asterisk of mandatory questions is set within the css "asterisk" class. To hide it:
*Open the template editor
*Open the template editor
Line 50: Line 60:
*Add the css ".asterisk {display: none;}" into the css stylesheet area.
*Add the css ".asterisk {display: none;}" into the css stylesheet area.


<!--T:15-->
'''Earlier Versions'''
'''Earlier Versions'''
*Open qanda.php in your text editor
*Open qanda.php in your text editor
Line 58: Line 69:
**modified: // $qtitle = '<span class=\'asterisk\'>'.$clang->gT('*').'</span>'.$qtitle;
**modified: // $qtitle = '<span class=\'asterisk\'>'.$clang->gT('*').'</span>'.$qtitle;


==How can I embed a flash file?==
==How can I embed a flash file?== <!--T:16-->


<!--T:17-->
First go to [[Global settings]] and deactivate the XSS-filter. Please also read up in the implications deactivating that filter. The following steps won't work if the filter is active.
First go to [[Global settings]] and deactivate the XSS-filter. Please also read up in the implications deactivating that filter. The following steps won't work if the filter is active.
#Navigate to the place in your survey where you want insert your Flash file. This can be anywhere where you can use the integrated HTML editor, for example in questions, subquestions, answers, survey welcome/end text and many more.
#Navigate to the place in your survey where you want insert your Flash file. This can be anywhere where you can use the integrated HTML editor, for example in questions, subquestions, answers, survey welcome/end text and many more.
Line 67: Line 79:
#If you clicked the 'Browse server' button you will be presented with a file browser and on the bottom an file upload field. Choose now an existing file or upload a file first.
#If you clicked the 'Browse server' button you will be presented with a file browser and on the bottom an file upload field. Choose now an existing file or upload a file first.


<!--T:18-->
That's it! If you find this description incomplete please update it accordingly.
That's it! If you find this description incomplete please update it accordingly.


==How to remove one of these texts from my survey==
==How to remove one of these texts from my survey== <!--T:19-->


==="There are X questions"===
==="There are X questions"=== <!--T:20-->


==="A note on privacy..."===
==="A note on privacy..."=== <!--T:21-->


===question code===
===question code=== <!--T:22-->


<!--T:23-->
All these texts are inserted at the template you are using by [http://docs.limesurvey.org/tiki-index.php?page=Template+editor&structure;=English+Instructions+for+LimeSurvey#Replacements_Field_Strings placeholders]. You can easily remove them. Go to the [http://docs.limesurvey.org/tiki-index.php?page=Template+editor&structure;=English+Instructions+for+LimeSurvey Template Editor] and remove the {THEREAREXQUESTIONS} / {PRIVACYMESSAGE} / {QUESTION_CODE} placeholder(s).
All these texts are inserted at the template you are using by [http://docs.limesurvey.org/tiki-index.php?page=Template+editor&structure;=English+Instructions+for+LimeSurvey#Replacements_Field_Strings placeholders]. You can easily remove them. Go to the [http://docs.limesurvey.org/tiki-index.php?page=Template+editor&structure;=English+Instructions+for+LimeSurvey Template Editor] and remove the {THEREAREXQUESTIONS} / {PRIVACYMESSAGE} / {QUESTION_CODE} placeholder(s).


=Survey configuration=
=Survey configuration= <!--T:24-->


==How do I create a survey which is open to everyone?==
==How do I create a survey which is open to everyone?== <!--T:25-->


<!--T:26-->
To make a survey public to everyone you should:
To make a survey public to everyone you should:
* not [http://docs.limesurvey.org/tiki-index.php?page=Tokens&structure;=English+Instructions+for+LimeSurvey#How_to_activate_tokens_ create a token table] (if there is one, drop it)
* not [http://docs.limesurvey.org/tiki-index.php?page=Tokens&structure;=English+Instructions+for+LimeSurvey#How_to_activate_tokens_ create a token table] (if there is one, drop it)
Line 89: Line 104:
* at survey settings set "[http://docs.limesurvey.org/tiki-index.php?page=Creating+a+new+survey&structure;=English+Instructions+for+LimeSurvey#Presentation_amp_Navigation list this survey publicly]"
* at survey settings set "[http://docs.limesurvey.org/tiki-index.php?page=Creating+a+new+survey&structure;=English+Instructions+for+LimeSurvey#Presentation_amp_Navigation list this survey publicly]"


<!--T:27-->
Your survey should then be listed at the root page of your limesurvey installation. You can publish the link to the survey on your website/blog and everyone can take the survey without restrictions.
Your survey should then be listed at the root page of your limesurvey installation. You can publish the link to the survey on your website/blog and everyone can take the survey without restrictions.


==How can I stop the system from sending confirmation emails==
==How can I stop the system from sending confirmation emails== <!--T:28-->


<!--T:29-->
If you are [http://docs.limesurvey.org/tiki-index.php?page=Tokens&structure;=English+Instructions+for+LimeSurvey#Email_settings using tokens] and a participant fills out the survey, a confirmation email is sent to his/her email address. If you don't want this message to be sent just delete the whole ''confirmation email'' subject and message. You have to [http://docs.limesurvey.org/tiki-index.php?page=First+Login+%2F+You+user+preferences&structure;=English+Instructions+for+LimeSurvey#X._Source_code_mode: switch to source code mode] to be able to delete all the text. Save the empty message and no confirmation emails should be sent anymore.
If you are [http://docs.limesurvey.org/tiki-index.php?page=Tokens&structure;=English+Instructions+for+LimeSurvey#Email_settings using tokens] and a participant fills out the survey, a confirmation email is sent to his/her email address. If you don't want this message to be sent just delete the whole ''confirmation email'' subject and message. You have to [http://docs.limesurvey.org/tiki-index.php?page=First+Login+%2F+You+user+preferences&structure;=English+Instructions+for+LimeSurvey#X._Source_code_mode: switch to source code mode] to be able to delete all the text. Save the empty message and no confirmation emails should be sent anymore.


=Help, I accidentally...=
=Help, I accidentally...= <!--T:30-->


==I forgot my admin password. How do I reset it?==
==I forgot my admin password. How do I reset it?== <!--T:31-->
# For version 1.47 to 1.53 only: Download [[Media:resetadminpw.php|this file]] and copy it to /<your limesurveydir>/admin/install/ .
# For version 1.47 to 1.53 only: Download [[Media:resetadminpw.php|this file]] and copy it to /<your limesurveydir>/admin/install/ .
# For version 1.7 or later: Restore your /<your limesurveydir>/admin/install/ directory from the download package
# For version 1.7 or later: Restore your /<your limesurveydir>/admin/install/ directory from the download package
Line 103: Line 120:
# After removing the /install directory again you should be able to login with $defaultuser (Default: admin) and $defaultpass (Default: password) set in config.php.
# After removing the /install directory again you should be able to login with $defaultuser (Default: admin) and $defaultpass (Default: password) set in config.php.


==How can I restore data from a deactivated survey?==
==How can I restore data from a deactivated survey?== <!--T:32-->


<!--T:33-->
We recommend to always use the time-out option instead of deactivating a survey. If you closed your survey accidentally it is important that you don't change anything in the survey.
We recommend to always use the time-out option instead of deactivating a survey. If you closed your survey accidentally it is important that you don't change anything in the survey.


<!--T:34-->
Then, and only then the following steps will work:
Then, and only then the following steps will work:
#Activate your survey again
#Activate your survey again
Line 114: Line 133:
#Click at the "Import responses" button.
#Click at the "Import responses" button.


==I deleted a question/question group/survey!==
==I deleted a question/question group/survey!== <!--T:35-->


<!--T:36-->
This is bad luck. If you delete it, it is really gone. In that case only a backup will help you (which of course you did regularly, didn't you?).
This is bad luck. If you delete it, it is really gone. In that case only a backup will help you (which of course you did regularly, didn't you?).


=Hard- and Software requirements=
=Hard- and Software requirements= <!--T:37-->


<!--T:38-->
For general requirements please refer to our [http://docs.limesurvey.org/tiki-index.php?page=Installation&structure;=English+Instructions+for+LimeSurvey#Make_sure_you_can_use_LimeSurvey_on_your_website installation instructions].
For general requirements please refer to our [http://docs.limesurvey.org/tiki-index.php?page=Installation&structure;=English+Instructions+for+LimeSurvey#Make_sure_you_can_use_LimeSurvey_on_your_website installation instructions].


==What limitations does LimeSurvey have...==
==What limitations does LimeSurvey have...== <!--T:39-->


=== ...regarding speed===
=== ...regarding speed=== <!--T:40-->


<!--T:41-->
There is no existing speed limit on LimeSurvey. It all depends on how fast your server and your connection is. If you expect a large number of users within a short time and you are not sure if your server can handle this check our forum for according topics about other users' experience.
There is no existing speed limit on LimeSurvey. It all depends on how fast your server and your connection is. If you expect a large number of users within a short time and you are not sure if your server can handle this check our forum for according topics about other users' experience.


=== ...regarding survey size===
=== ...regarding survey size=== <!--T:42-->


<!--T:43-->
Note: 'Survey size' refers to the maximmum number of questions (and answers) in your survey - '''don't confuse this with the number of replies on your survey (there is no limitation on that)'''. Theoretically there would also be no limit on the maximum number of questions/answers in LimeSurvey. But the database engine you are using has several limits. The most important one is the limit on the number of fields(columns) in the result table.
Note: 'Survey size' refers to the maximmum number of questions (and answers) in your survey - '''don't confuse this with the number of replies on your survey (there is no limitation on that)'''. Theoretically there would also be no limit on the maximum number of questions/answers in LimeSurvey. But the database engine you are using has several limits. The most important one is the limit on the number of fields(columns) in the result table.
*MySQL ISAM: The sum of the lengths of the VARCHAR and CHAR columns in a table may be up to 64KB.
*MySQL ISAM: The sum of the lengths of the VARCHAR and CHAR columns in a table may be up to 64KB.
Line 136: Line 159:
*Postgres: Maximum number of 250-1600 columns depending on column types. The maximum number of columns can be quadrupled by increasing the default block size to 32k. See [[Installation FAQ]] and [http://www.postgresql.org/docs/faqs.FAQ.html#item4.4 PostgreSQL FAQ].
*Postgres: Maximum number of 250-1600 columns depending on column types. The maximum number of columns can be quadrupled by increasing the default block size to 32k. See [[Installation FAQ]] and [http://www.postgresql.org/docs/faqs.FAQ.html#item4.4 PostgreSQL FAQ].


<!--T:44-->
The mySQL ISAM engine is the most tricky one (see [http://dev.mysql.com/doc/refman/5.0/en/column-count-limit.html mysql documentation for more information]). As it allows only up to 65,535 bytes per row and utf8 characters can require up to three bytes per character the maximum may be only 21,844 characters (but this depends on your DB encoding).
The mySQL ISAM engine is the most tricky one (see [http://dev.mysql.com/doc/refman/5.0/en/column-count-limit.html mysql documentation for more information]). As it allows only up to 65,535 bytes per row and utf8 characters can require up to three bytes per character the maximum may be only 21,844 characters (but this depends on your DB encoding).


<!--T:45-->
You can roughly calculate the size of your survey like this:
You can roughly calculate the size of your survey like this:
*Every multiple numerical question: 20 chars '''for each answer'''
*Every multiple numerical question: 20 chars '''for each answer'''
Line 144: Line 169:
*Add 10% for the usual overhead
*Add 10% for the usual overhead


==How to increase the maximum number of columns in PostgreSQL==
==How to increase the maximum number of columns in PostgreSQL== <!--T:46-->


<!--T:47-->
In case your survey contains too many questions you can define a different block size in PostgreSQL so it is possible to create more columns. This might be tricky because you have to recompile PostgreSQL and set BLCKSZ to a higher value, like 16kiB or 32kiB. Watch for the configuration option "--with-blocksize=BLOCKSIZE". For details see the archives of the PostgreSQL mailing list or ask there (pgsql-patches(at)postgresql(dot)org).
In case your survey contains too many questions you can define a different block size in PostgreSQL so it is possible to create more columns. This might be tricky because you have to recompile PostgreSQL and set BLCKSZ to a higher value, like 16kiB or 32kiB. Watch for the configuration option "--with-blocksize=BLOCKSIZE". For details see the archives of the PostgreSQL mailing list or ask there (pgsql-patches(at)postgresql(dot)org).


<!--T:48-->
Instructions for Debian (thanks to Martin Pitt):
Instructions for Debian (thanks to Martin Pitt):


<!--T:49-->
<syntaxhighlight lang="c" enclose="div"> sudo apt-get build-dep postgresql-8.3
<syntaxhighlight lang="c" enclose="div"> sudo apt-get build-dep postgresql-8.3


<!--T:50-->
apt-get source postgresql-8.3
apt-get source postgresql-8.3


<!--T:51-->
cd postgresql-8.3-*
cd postgresql-8.3-*


<!--T:52-->
debian/rules patch
debian/rules patch


<!--T:53-->
sensible-editor build-tree/postgresql-8.3.5/src/include/pg_config_manual.h
sensible-editor build-tree/postgresql-8.3.5/src/include/pg_config_manual.h


<!--T:54-->
dpkg-buildpackage -us -uc -b -nc</syntaxhighlight>
dpkg-buildpackage -us -uc -b -nc</syntaxhighlight>


==Survey participants get kicked out to the Surveys List page part way through. What can I do?==
==Survey participants get kicked out to the Surveys List page part way through. What can I do?== <!--T:55-->


<!--T:56-->
If you have a particularly long survey, and you find that your users can access a survey, and get part way through completing it, but then seem to get kicked out to the Surveys List page check your PHP settings. If your host is using the '''Suhosin extension for Apache''' it may be set to be too limiting on a couple of settings.
If you have a particularly long survey, and you find that your users can access a survey, and get part way through completing it, but then seem to get kicked out to the Surveys List page check your PHP settings. If your host is using the '''Suhosin extension for Apache''' it may be set to be too limiting on a couple of settings.


<!--T:57-->
For example the two settings "suhosin.post.max_vars" and "suhosin.request.max_vars" are both set to a value of 200 by default. Increase those settings both to 400 or higher so users can complete and submit long surveys.
For example the two settings "suhosin.post.max_vars" and "suhosin.request.max_vars" are both set to a value of 200 by default. Increase those settings both to 400 or higher so users can complete and submit long surveys.


<!--T:58-->
If you still have problems, try switching the module to simulation_mode (and so basically deactivate it), as the maximum value always depends on your particular survey.
If you still have problems, try switching the module to simulation_mode (and so basically deactivate it), as the maximum value always depends on your particular survey.


==Fatal error: Allowed memory size==
==Fatal error: Allowed memory size== <!--T:59-->


<!--T:60-->
Depending on your server configuration you might run into memory problems being reported by an error like ''"Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 233472 bytes) in /path/to/htdocs/limesurvey/filename.php on line 7296"''.
Depending on your server configuration you might run into memory problems being reported by an error like ''"Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 233472 bytes) in /path/to/htdocs/limesurvey/filename.php on line 7296"''.


<!--T:61-->
You can try to raise the limit by [http://docs.limesurvey.org/Optional+settings&structure;=English+Instructions+for+LimeSurvey#Resources adding an optional setting to Limesurvey's config file].
You can try to raise the limit by [http://docs.limesurvey.org/Optional+settings&structure;=English+Instructions+for+LimeSurvey#Resources adding an optional setting to Limesurvey's config file].


<!--T:62-->
Please mind that such local settings by an application can always be overruled by global server settings. To increase the memory limit to 128M directly on your server you could try adding:
Please mind that such local settings by an application can always be overruled by global server settings. To increase the memory limit to 128M directly on your server you could try adding:
*memory_limit = 128M to your server's main php.ini file (recommended, if you have access)
*memory_limit = 128M to your server's main php.ini file (recommended, if you have access)
Line 182: Line 221:
*ini_set('memory_limit', '128M'); in your config.php
*ini_set('memory_limit', '128M'); in your config.php


=Email problems=
=Email problems= <!--T:63-->


</translate>
</translate>

Revision as of 10:52, 14 April 2013

Getting started

If you don't want to read half the manual to get a feeling what can be done with Limesurvey we recommend to watch some videos (see below).

After that the Creating surveys - Introduction manual page might be a good start.

I need a quick introduction for LimeSurvey

For a first start have a look at our very basic LimeSurvey Video-Tutorial.

There is another tutorial which shows you how to get started with using Lime Survey to conduct online surveys. In this video we'll create our first survey, deliver it to a user and then view the submitted results.

There are some more videos on YouTube:

Limesurvey:

Old PHP-surveyor videos:

Survey design and layout

How do I get rid of the * (red asterisk) of mandatory questions?

In LimeSurvey Version 1.80 and above the red asterisk of mandatory questions is set within the template.css file ("asterisk" class). To hide it:

  • Open the template editor
  • Create a copy of the template you wish to modify
  • Select the "template.css" file and search for the asterix class
  • Add the following line at the end of the asterix class".asterisk {display: none;}".
  • Save template.css
  • Clear your browser cache so that the edited template.css is reloaded and not taken from cache.

In LimeSurvey Version 1.53 the red asterisk of mandatory questions is set within the css "asterisk" class. To hide it:

  • Open the template editor
  • Select the template you wish to modify so that the asterisk doesn't show
  • Select the "startpage.pstpl" file
  • Add the css ".asterisk {display: none;}" into the css stylesheet area.

Earlier Versions

  • Open qanda.php in your text editor
  • Search for the string "asterisk"
  • Comment out this line with two slashes "//" at the beginning of the line
  • Example:
    • original: $qtitle = ''.$clang->gT('*').''.$qtitle;
    • modified: // $qtitle = ''.$clang->gT('*').''.$qtitle;

How can I embed a flash file?

First go to Global settings and deactivate the XSS-filter. Please also read up in the implications deactivating that filter. The following steps won't work if the filter is active.

  1. Navigate to the place in your survey where you want insert your Flash file. This can be anywhere where you can use the integrated HTML editor, for example in questions, subquestions, answers, survey welcome/end text and many more.
  2. Open the full-screen editor mode by clicking the 'LimeFitWin' button on the editor tool-bar.
  3. On the full-screen editor tool-bar you will find a little button with a Flash symbol. Click on it. A dialog will open.
  4. In this dialog you can give either the path to an existing Flash file somewhere OR you click the 'Browse server' button.
  5. If you clicked the 'Browse server' button you will be presented with a file browser and on the bottom an file upload field. Choose now an existing file or upload a file first.

That's it! If you find this description incomplete please update it accordingly.

How to remove one of these texts from my survey

"There are X questions"

"A note on privacy..."

question code

All these texts are inserted at the template you are using by placeholders. You can easily remove them. Go to the Template Editor and remove the {THEREAREXQUESTIONS} / {PRIVACYMESSAGE} / {QUESTION_CODE} placeholder(s).

Survey configuration

How do I create a survey which is open to everyone?

To make a survey public to everyone you should:

Your survey should then be listed at the root page of your limesurvey installation. You can publish the link to the survey on your website/blog and everyone can take the survey without restrictions.

How can I stop the system from sending confirmation emails

If you are using tokens and a participant fills out the survey, a confirmation email is sent to his/her email address. If you don't want this message to be sent just delete the whole confirmation email subject and message. You have to switch to source code mode to be able to delete all the text. Save the empty message and no confirmation emails should be sent anymore.

Help, I accidentally...

I forgot my admin password. How do I reset it?

  1. For version 1.47 to 1.53 only: Download this file and copy it to /<your limesurveydir>/admin/install/ .
  2. For version 1.7 or later: Restore your /<your limesurveydir>/admin/install/ directory from the download package
  3. Execute resetadminpw.php using your browser by pointing it to
    http://www.your_domain.com/your_limesurvey_dir/admin/install/resetadminpw.php
    
  4. After removing the /install directory again you should be able to login with $defaultuser (Default: admin) and $defaultpass (Default: password) set in config.php.

How can I restore data from a deactivated survey?

We recommend to always use the time-out option instead of deactivating a survey. If you closed your survey accidentally it is important that you don't change anything in the survey.

Then, and only then the following steps will work:

  1. Activate your survey again
  2. Go to the "Browse responses for this survey" menu.
  3. Click at the "Import answers from a deactivated survey table" button.
  4. Choose your source table.
  5. Click at the "Import responses" button.

I deleted a question/question group/survey!

This is bad luck. If you delete it, it is really gone. In that case only a backup will help you (which of course you did regularly, didn't you?).

Hard- and Software requirements

For general requirements please refer to our installation instructions.

What limitations does LimeSurvey have...

...regarding speed

There is no existing speed limit on LimeSurvey. It all depends on how fast your server and your connection is. If you expect a large number of users within a short time and you are not sure if your server can handle this check our forum for according topics about other users' experience.

...regarding survey size

Note: 'Survey size' refers to the maximmum number of questions (and answers) in your survey - don't confuse this with the number of replies on your survey (there is no limitation on that). Theoretically there would also be no limit on the maximum number of questions/answers in LimeSurvey. But the database engine you are using has several limits. The most important one is the limit on the number of fields(columns) in the result table.

  • MySQL ISAM: The sum of the lengths of the VARCHAR and CHAR columns in a table may be up to 64KB.
  • MySQL InnoDB: Maximum number of 1000 columns
  • MS SQL Server 2000: Maximum number of 1024 columns
  • Postgres: Maximum number of 250-1600 columns depending on column types. The maximum number of columns can be quadrupled by increasing the default block size to 32k. See Installation FAQ and PostgreSQL FAQ.

The mySQL ISAM engine is the most tricky one (see mysql documentation for more information). As it allows only up to 65,535 bytes per row and utf8 characters can require up to three bytes per character the maximum may be only 21,844 characters (but this depends on your DB encoding).

You can roughly calculate the size of your survey like this:

  • Every multiple numerical question: 20 chars for each answer
  • Every multiple choice & array question answers: 5 chars for each answer
  • Every other question type: 5 chars
  • Add 10% for the usual overhead

How to increase the maximum number of columns in PostgreSQL

In case your survey contains too many questions you can define a different block size in PostgreSQL so it is possible to create more columns. This might be tricky because you have to recompile PostgreSQL and set BLCKSZ to a higher value, like 16kiB or 32kiB. Watch for the configuration option "--with-blocksize=BLOCKSIZE". For details see the archives of the PostgreSQL mailing list or ask there (pgsql-patches(at)postgresql(dot)org).

Instructions for Debian (thanks to Martin Pitt):

 sudo apt-get build-dep postgresql-8.3

apt-get source postgresql-8.3

cd postgresql-8.3-*

debian/rules patch

sensible-editor build-tree/postgresql-8.3.5/src/include/pg_config_manual.h

dpkg-buildpackage -us -uc -b -nc

Survey participants get kicked out to the Surveys List page part way through. What can I do?

If you have a particularly long survey, and you find that your users can access a survey, and get part way through completing it, but then seem to get kicked out to the Surveys List page check your PHP settings. If your host is using the Suhosin extension for Apache it may be set to be too limiting on a couple of settings.

For example the two settings "suhosin.post.max_vars" and "suhosin.request.max_vars" are both set to a value of 200 by default. Increase those settings both to 400 or higher so users can complete and submit long surveys.

If you still have problems, try switching the module to simulation_mode (and so basically deactivate it), as the maximum value always depends on your particular survey.

Fatal error: Allowed memory size

Depending on your server configuration you might run into memory problems being reported by an error like "Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 233472 bytes) in /path/to/htdocs/limesurvey/filename.php on line 7296".

You can try to raise the limit by adding an optional setting to Limesurvey's config file.

Please mind that such local settings by an application can always be overruled by global server settings. To increase the memory limit to 128M directly on your server you could try adding:

  • memory_limit = 128M to your server's main php.ini file (recommended, if you have access)
  • memory_limit = 128M to a php.ini file in the LimeSurvey root
  • php_value memory_limit 32M in a .htaccess file in the LimeSurvey root
  • ini_set('memory_limit', '128M'); in your config.php

Email problems