haio

http://moeffju.net/blog/using-bigint-columns-in-rails-migrations

haio

It is better to remain silent and be thought a fool, than to speak out and remove all doubt

haio

Good design should make a product useful

haio

nil 
boolean  --false 和 nil为假，其余为真
number   --lua 中没有整数
string   --字符串值不可修改 "10" + 1 == 11
         --"hello" + 1 ERROR
         --"hello" + "world" ERROR
         --"i want" .. 10
function
userdata
thread

haio

mysql -u -p database < file.sql
mysql -uroot -psss -h 1.1.1.1 -P3306 

haio

adduser newuser
passwd newuser
visudo
在root ALL=(ALL)  ALL下面加一行
  newuser ALL=(ALL) ALL

haio

rvm pkg install openssl
rvm reinstall 1.9.3 --with-openssl-dir=$rvm_path/usr

haio

Ubuntu:
/etc/network/interfaces

auto lo$                                                                       
iface lo inet loopback$                                                        
# The primary network interface$                                               
auto eth0$                                                                     
#iface eth0 inet dhcp$                                                         
iface eth0 inet static$                                                        
address 1.1.8.8$                                                               

haio

sudo apt-get install openssh-server
yum install openssh-server
service sshd start

haio

:set nu
:set ruler