N.C. Gen. Stat. § 7A-63

Each district attorney shall be entitled to the number of full-time assistant district attorneys set out in this Subchapter to be appointed by the district attorney, to serve at the district attorney's pleasure. A vacancy in the office of assistant district attorney shall be filled in the same manner as the initial appointment. An assistant district attorney shall take the same oath of office as the district attorney, and shall perform such duties as may be assigned by the district attorney. The district attorney shall devote full time to the duties of the office and shall not engage in the private practice of law during his or her term.