Hallo, Benjamin,
Du meintest am 07.12.10:
I only see a mask where I can fill in old and new name for merging.
There should be a checkbox that says "Delete old user". Check it and leave the new name blank, and it will prompt you to merge the user to "Anonymous" and delete it (I don't know how well it will work if the account has made edits).
In this special case: spamming users
I had tried the way you propose here and didn't know what would happen when merging to "anonymous" - I wanted to delete, not to merge ...
But that way seems to work as expected.
And I still miss the array of all users (just as shown in the example). It's no fun working with "copy & paste" ...
Honestly, you're better off taking ?ukasz's and Thomas' advice. Deleting users is a really pointless endeavor.
Yes - I've tried the way via "phpMyAdmin", and it didn't please me ...
And the result messages from "merge to anonymous" show that there is more to be done than only deleting the entry in the "user" table.
Viele Gruesse! Helmut