After the business license. Merchants to the competent authorities to review the relevant documents, to be licensed, the documents down, and then apply for the door, or after the door, go to the license, due to other reasons and procedures are incomplete, the license can not be done down, the door is good after the use of the head, the loss is also relatively large, so do a good job of business license and then apply for the door. Nanjing, referred to as "Ning", the ancient name of Jinling, Jiankang, the capital of Jiangsu Province, sub-provincial city, megacity, Nanjing metropolitan area core city, the State Council approved the determination of the eastern region of China's important central city, the country's important scientific research and education bases and comprehensive transportation hub.