It's a simple problem, I think, but I don't know what to do. After replace the separators in my Object "schlagwort", there are two columns. But I just want to see the right one with the nice "+" between the words. Cause... That's the reason why I replace the separators. Can you help me?
It looks like you are using a list box with an additional expression. This is similar to having a chart with dimension schlagwort and your expression, and you will see both columns.
You can use an expression instead of your field in the list box (choose <expression> from the field selection drop down in list box general properties), but it is better to create a new field in your load script that does the replace (or replace your original field with your modified):
replace(...) as schlagwort,
If you want the list box solution:
=aggr( replace(...), schlagwort)
[You'll need to use your complete replace expression of course].