Sheriff 's Department spokesman Chris Saunders said the man told them he was frustrated by the Postal Service 's response to an accident involving a postal vehicle .
According to Saunders , the gunman said he was frustrated by the U.S. Postal Service 's response to an accident involving a postal vehicle .
1nf- must have a primary key and no repeating groups 2nf- 1nf and no partial dependencies 3nf- 2nf and no transitive dependencies