Mysqli - error files dialog

[wolfsauge]

I simply have problems to understand the documentation.
I only need to import the guestbook entries, not the other stuff, so I am a little confused about what to do. Anyway I tried and failed, phpMyAdmin reported an error, which I do not understand and so cannot resolve.
I just give up, its only three entries but meanwhile hours trying to understand what to do and yet finally failing.
Anyway thanks for trying to help and all your advice!
Have a nice Easter
Best wishes
Dirk