Eigentlich mehr fürs Archiv, Select Case in stored procedure:
SELECT @gb = CASE WHEN @zaehler = 1 THEN 'GB 1' WHEN @zaehler = 2 THEN 'GB 2' WHEN @zaehler = 3 THEN 'GB 3' WHEN @zaehler = 4 THEN 'GB 4' WHEN @zaehler = 5 THEN 'GB 5' END