user: Question: When Nanhai 南海 is the commandery what is the commandery capital?
Columns: ['Province', 'Provincial capital', 'Commandery', 'Commandery capital', 'No. of counties']
Types: ['text', 'text', 'text', 'text', 'real']
Sample row: ['Yang 揚', 'Jianye 建業', 'Danyang 丹陽', 'Jianye 建業', 16.0]
SQL:

assistant: SELECT "Commandery capital" FROM "Table" WHERE "Commandery" = 'Nanhai 南海';