S sjm Unregistered / Unconfirmed GUEST, unregistred user! 2007-11-03 #1 Update tb_user Set admin = (NOT admin) 我的本意是想让字段admin（bit类型，非0即1）的值修改为其相反值，怎么执行后没反应？
S sjm Unregistered / Unconfirmed GUEST, unregistred user! 2007-11-03 #2 改成： Update tb_user Set admin = NOT(admin) 好像也不起作用。
E errorcode Unregistered / Unconfirmed GUEST, unregistred user! 2007-11-03 #3 update tb_user set admin = ~admin
