[20230417]sqlplus warpped word_warp.txt

--//今天调试sql脚本时遇到的情况,设置word_warp 如果前面有空格输出会丢失的情况.
--//WARPPED用于折行，WARPPED按指定长度折行，WORD_WARPPED值按照完整字符串折行
--//但是可能遇到奇怪的问题前面的空格不显示的问题.通过例子说明.

1.环境:
SCOTT@book> @ ver1
PORT_STRING                    VERSION        BANNER
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

2.测试:
SCOTT@book> select dname from dept where deptno = 10;
DNAME
--------------
ACCOUNTING

SCOTT@book> column dname format a6
SCOTT@book> select dname from dept where deptno = 10;
DNAME
------
ACCOUN
TING
--//缺省wrapped.出现折行.

SCOTT@book> column dname format a6 word_wrap
SCOTT@book> select dname from dept where deptno = 10;
DNAME
------
ACCOUN
TING
--//这样看不出来,单词ACCOUNTING有点长!!写成如下:

SCOTT@book> select 'hello how are you' dname from dept where deptno = 10;
DNAME
------
hello
how
are
you
--//基本按照词分隔.

SCOTT@book> column dname format a6 wrapped
SCOTT@book> select 'hello how are you' dname from dept where deptno = 10;
DNAME
------
hello
how ar
e you
--//没有按照词分隔.

--//如果开始部分存在空格呢?
SCOTT@book> select lpad(' ',10,' ')||dname dname from dept where deptno = 10;
DNAME
------

    AC
COUNTI
NG


SCOTT@book> column dname format a6 word_wrapped
SCOTT@book> select lpad(' ',10,' ')||dname dname from dept where deptno = 10;
DNAME
------
ACCOUN
TING
--//输出丢失前面的空格!!