Upgrading from a previous version

Additional pages:{toc}

Before you start...

... read this because it is very important: Always backup the files and the database of your current installation!

You can do this using a database administration tool like phpMyAdmin and a file manager! If you don't know how to do this, you should not proceed further and ask someone who knows.

Recommendation to use ComfortUpdate

The easiest/safest way to upgrade is to use our ComfortUpdate service.

Upgrade instructions (from 2.x or newer to any later version)

Please follow these instructions:

• Backup your files and database (did we already mention that?).
• Delete all the old files/folders except for:
  • /application/config/security.php -Important!! This is the key to all encrypted data in LimeSurvey (version 4 and later)
  • /application/config/config.php;
  • /upload directory

Note: If you have any customized templates in /upload/templates, make sure you 'refresh' those with any changes that come with the new LimeSurvey version. The easiest way to check for such changes is to file-compare your old template with the new version of the default template. If you see any differences other than your customizations, a refresh is needed.

• Copy the new files from the new LimeSurvey package to the existing location.
• Open the admin page in your browser (e.g. https://www.example.com/limesurvey/admin) and check if a database scheme upgrade is necessary.
• After the upgrade: Clear your browser cache and cookies!

Upgrading using CLI

You can upgrade the database via the PHP CLI: php application/commands/console.php updatedb. This allows you to set up an auto-upgrade system via command line (for example, in a crontab), although it is not recommended.

Failed database upgrade after manual update/ComfortUpdate

Sometimes, even though you did everything correct, things don't work out they are supposed to during database upgrade. That may happen because of various reasons: Different database versions, unexpected data formats or contents, unusual configurations or anything else that did not show up in our tests (yes, we test a lot!)

If you have an error during database update and your LimeSurvey instance ends up in an unusable state, you want to go back to the previous version. This assumes that you still have the database and file backup, either from your regular backup or the one created by Comfortupdate.

Please execute the following steps:

• Backup the existing LimeSurvey directory and database (yes, again - we will call this the 2nd backup)
• Restore files to the existing directory (just overwriting them is fine) from the original (1st) backup.
• Delete the old database and restore the database from the original (1st) backup.

That's it. Everything should be back to normal.

A note about reporting this issue:

If you run into a problem like this, please always report this in our bug tracker at https://bugs.limesurvey.org

A bug not reported is a bug not fixed. Please don't just rely on other people reporting it. If you see that the bug is already reported, you can also help to raise the bug priority by marking it as 'Yes, this bug affects me' in the bug tracker.

FAQ

Can I upgrade even if I have active surveys?

Yes, you can. Exceptions may be mentioned in the thorough instructions above. We strongly advise to test your surveys after upgrade to check if your design templates still work alright.

How to convert *.sql/*.csv survey structure files to the latest LimeSurvey version?

Install version 1.50, import the file, and export the survey structure to the newer .csv format. Then install the latest Version 2.x and import the .csv format and export it to the current .lss format.

Survey theme incompatibility

With certain major version updates any custom survey themes will not be compatible, anymore:

• Update from LimeSurvey 2.6 or lower to LimeSurvey 2.50
• Update from LimeSurvey 5.x or lower to LimeSurvey 6.x

Error "Multiple primary key defined" when updating MySQL database

If you encounter this error, please check the setting sql_generate_invisible_primary_key in your MySQL server variables. This is most likely set to ON, but should be set to OFF. Then restore your database from the backup (as explained above) and try again.