NULL, empty string and values

From LimeSurvey Manual

Details on the difference between NULL, empty string and values in the database response table.


DECIMAL and DATE cannot be "empty string".

TODO: Exclusive option

TODO: Slider

Example: Slider with default value is NULL if not shown.

TODO: Relevance equation 0 with default value? Always hidden with default value?

TODO: Hidden by attribute VS hidden by relevance equation.