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Your LimeSurvey version: LimeSurvey Community Edition Version 5.3.14+220516
Own server or LimeSurvey hosting: Own Server
Survey theme/template: -
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Hey guys,

I'm developing a plugin. If an user participates on the survey, I can see all the responses on the page "responses" in a table (with columns like "completed" etc.).
But I want to write additional information to the database so the table shows another custom column, e.g. "successful" where PHP should define if a user gets a true or false (based on some variables). 
My approach is to use the afterSurveyComplete-Event. I can already show the responses via $this->pluginManager->getAPI()->getResponse($surveyId, $responseId);
But how can I set an additional variable there? How to write data to the database?

Greetings!

To add a new column to your responses tabel, you can also add a hidden question (text) with the question code "succesful"

That would be possible, yes. But I want that a limesurvey survey creator only needs to install my plugin and do not alter its survey (by adding additional questions).
Is there another way?

Well, yes, but then you would indeed need a plugin.

I am not good at that, possibly one of the other experts that hang around here may be able to help you.

Tammo

Thank you for your answers!
Yes indeed, my whole topic is about me developing a plugin