师从‘百测’besttest 今日牛老师布置了一个作业,生成一个随机密码,且要包含大写字母.小写字母.数字和特殊字符,且不能重复. 想着先生成密码,然后用各字符去检查是否存在,使用for嵌套循环. import string l = [','123!@#qweA'] i = 0 n = 3 while i < n: # 从a-zA-Z0-9特殊字符中生成指定数量的随机字符 #pwd = ''.join(random.sample(string.ascii_letters + string.dig
当没有用 EXISTS 引入子查询时,在选择列表中只能指定一个表达式.比如 select * from T_Employee where FNumber not in ( select top 5* from T_Employee order by FSalary desc)order by FSalary 在sql中执行出现错误 更正:select * from T_Employee where FNumber not in (select top 5 FNumber from T_Em