Longhaired dachshunds:

The sleek, glistening, often slightly wavy hair is longer under the neck
and on the chest,underside of the body, ears and legs.  The coat gives
the dog an elegant appearance.  Short hair on the ear is not desirable.  
Also not desirable and considered faults are hair that is long all over the
whole body, curly coat or pronounce parting on the back.

Their tail is a prolongation of the spine and the hair is at it's greatest
length here.  When the tail is extended, it looks like a flag.