因为有一次数据不小心关机，导致数据库crash之后，想尽各种方法最终recovery database 之后，可是发现原来的apache，PHP，Oracle建立的web server 却无法运行，在页面上总是提示ora-06550;pls-00553: character set name is not recognized 。 害的我费劲周折，浪费了3天多的时间才搞定这个问题。刚开始发现这个问题的时候就觉得是什么参数设置变动之后引发的错误。因为找不问题，一直非常郁闷，花了好久重新安装php和apache server。还是不行。最后在网络上看到set NLS_LANG AMERICAN_AMERICA.US7ASCII可以成功。

最后自己试了一下，果然奏效，我原来一直以为就是NLS_LANG American_America.WE8ISO8859P1。现在才明白。下面试我操作的过程

[oracle@ccdevsvr php-4.3.6]$ su root
PassWord:
[root@ccdevsvr php-4.3.6]# set NLS_LANG AMERICAN_AMERICA.US7ASCII
[root@ccdevsvr php-4.3.6]# set
BASH=/bin/bash
BASH_ENV=/root/.bashrc
BASH_VERSINFO=([0]="2" [1]="05b" [2]="0" [3]="1" [4]="release" [5]="i686-pc-Linux-gnu")
BASH_VERSION='2.05b.0(1)-release'
COLORS=/etc/DIR_COLORS
COLUMNS=132
CVSROOT=/opt/class/jackey/cvsroot
DIRSTACK=()
EUID=0
GROUPS=()
G_BROKEN_FILENAMES=1
HISTFILE=/root/.bash_history
HISTFILESIZE=1000
HISTSIZE=1000
HOME=/root
HOSTNAME=ccdevsvr
HOSTTYPE=i686
IFS=$' tn'
INPUTRC=/etc/inputrc
LANG=en_US.UTF-8
LD_LIBRARY_PATH=:/u01/prodUCt/8.1.7/lib
LESSOPEN='/usr/bin/lesspipe.sh %s'
LINES=49
LOGNAME=oracle
LS_COLORS='no=00:fi=00:di=01;34:ln=01;36:pi=40;33:so=01;35:bd=40;33;01:cd=40;33;01:or=01;05;37;41:mi=01;05;37;41:ex=01;32:*.cmd=01;32:*.exe=01;32:*.com=01;32:*.BTm=01;32:*.bat=01;32:*.sh=01;32:*.csh=01;32:*.tar=01;31:*.tgz=01;31:*.arj=01;31:*.taz=01;31:*.lzh=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.gz=01;31:*.bz2=01;31:*.bz=01;31:*.tz=01;31:*.rpm=01;31:*.cpio=01;31:*.jpg=01;35:*.gif=01;35:*.bmp=01;35:*.xbm=01;35:*.XPm=01;35:*.png=01;35:*.tif=01;35:'
MACHTYPE=i686-pc-linux-gnu
MAIL=/var/spool/mail/root
MAILCHECK=60
NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1
OPTERR=1
OPTIND=1
ORACLE_BASE=/u01
ORACLE_HOME=/u01/product/8.1.7
ORACLE_SID=EMCDB
ORA_NLS=/u01/product/8.1.7/ocommon/nls/admin/data
ORA_NLS33=/u01/product/8.1.7/ocommon/nls/admin/data
OSTYPE=linux-gnu
PATH=/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:/usr/bin/X11:/usr/X11R6/bin:/root/bin
PIPESTATUS=([0]="0")
PPID=17922
PS1='
[u@h W]$ '
PS2='> '
PS4='+ '
PWD=/u01/php-4.3.6
QTDIR=/usr/lib/qt3-gcc3.2
SHELL=/bin/bash
SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor
SHLVL=4
SSH_ASKPASS=/usr/libexec/openssh/gnome-ssh-askpass
SUPPORTED=en_US.UTF-8:en_US:en
TERM=vt100
UID=0
USER=oracle
USERNAME=root
_=AMERICAN_AMERICA.US7ASCII
i=/etc/profile.d/which-2.sh
langfile=/root/.i18n
[root@ccdevsvr php-4.3.6]# set NLS_LANG=AMERICAN_AMERICA.US7ASCII
[root@ccdevsvr php-4.3.6]# set
BASH=/bin/bash
BASH_ENV=/root/.bashrc
BASH_VERSINFO=([0]="2" [1]="05b" [2]="0" [3]="1" [4]="release" [5]="i686-pc-linux-gnu")
BASH_VERSION='2.05b.0(1)-release'
COLORS=/etc/DIR_COLORS
COLUMNS=132
CVSROOT=/opt/class/jackey/cvsroot
DIRSTACK=()
EUID=0
GROUPS=()
G_BROKEN_FILENAMES=1
HISTFILE=/root/.bash_history
HISTFILESIZE=1000
HISTSIZE=1000
HOME=/root
HOSTNAME=ccdevsvr
HOSTTYPE=i686
IFS=$' tn'
INPUTRC=/etc/inputrc
LANG=en_US.UTF-8
LD_LIBRARY_PATH=:/u01/product/8.1.7/lib
LESSOPEN='/usr/bin/lesspipe.sh %s'
LINES=49
LOGNAME=oracle
LS_COLORS='no=00:fi=00:di=01;34:ln=01;36:pi=40;33:so=01;35:bd=40;33;01:cd=40;33;01:or=01;05;37;41:mi=01;05;37;41:ex=01;32:*.cmd=01;32:*.exe=01;32:*.com=01;32:*.btm=01;32:*.bat=01;32:*.sh=01;32:*.csh=01;32:*.tar=01;31:*.tgz=01;31:*.arj=01;31:*.taz=01;31:*.lzh=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.gz=01;31:*.bz2=01;31:*.bz=01;31:*.tz=01;31:*.rpm=01;31:*.cpio=01;31:*.jpg=01;35:*.gif=01;35:*.bmp=01;35:*.xbm=01;35:*.xpm=01;35:*.png=01;35:*.tif=01;35:'
MACHTYPE=i686-pc-linux-gnu
MAIL=/var/spool/mail/root
MAILCHECK=60
NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1
OPTERR=1
OPTIND=1
ORACLE_BASE=/u01
ORACLE_HOME=/u01/product/8.1.7
ORACLE_SID=EMCDB
ORA_NLS=/u01/product/8.1.7/ocommon/nls/admin/data
ORA_NLS33=/u01/product/8.1.7/ocommon/nls/admin/data
OSTYPE=linux-gnu
PATH=/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/u01/product/8.1.7/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:/usr/bin/X11:/usr/X11R6/bin:/root/bin
PIPESTATUS=([0]="0")
PPID=17922
PS1='[u@h W]$ '
PS2='> '
PS4='+ '
PWD=/u01/php-4.3.6
QTDIR=/usr/lib/qt3-gcc3.2
SHELL=/bin/bash
SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor
SHLVL=4
SSH_ASKPASS=/usr/libexec/openssh/gnome-ssh-askpass
SUPPORTED=en_US.UTF-8:en_US:en
TERM=vt100
UID=0
USER=oracle
USERNAME=root
_=NLS_LANG=AMERICAN_AMERICA.US7ASCII
i=/etc/profile.d/which-2.sh
langfile=/root/.i18n
[root@ccdevsvr php-4.3.6]#