python3 操作MYSQL實例及異常信息處理--用traceback模塊

# 用traceback模塊查看異常
import traceback import pymysql db = pymysql.connect(host='localhost', user='root', password='root', port=3306, db='spiders') cursor = db.cursor() try: sql = 'SELECT graph, brand_name FROM base_info'
    # 執行sql語句 
 cursor.execute(sql) result = cursor.fetchone() except: 
    # 輸出異常信息 
 traceback.print_exc() # 如果發生異常，則回滾 
 db.rollback() finally: # 最終關閉數據庫連接 
    db.close()