Oracle 为什么sqlplus变量在句点上的行为很有趣？

为什么sqplus变量在尝试使用句点后会表现得很滑稽

SQL> set define on
SQL> accept goo char prompt 'goo: ';
goo: mygoo
SQL> select '&goo' from dual;
old   1: select '&goo' from dual
new   1: select 'mygoo' from dual

MYGO
-----
mygoo

SQL> select '&goo something' from dual;
old   1: select '&goo something' from dual
new   1: select 'mygoo something' from dual

MYGOOSOMETHING
---------------
mygoo something

SQL> select '&goo.something' from dual;
old   1: select '&goo.something' from dual
new   1: select 'mygoosomething' from dual

MYGOOSOMETHIN
--------------
mygoosomething

SQL> select '&goo..something' from dual;
old   1: select '&goo..something' from dual
new   1: select 'mygoo.something' from dual

MYGOO.SOMETHIN
---------------
mygoo.something

为什么我要加倍月经？有更好的方法吗？

这一点都不好笑，但却是预期的默认行为

SET CONCAT字符是句点，除非将其设置为其他字符。如果要在替换变量之后添加句点，则必须使用两个连续的句点

如果将concat character设置为，例如，则句点正常工作：

如果将其设置回一个句点，它的行为将再次变得有趣：

最后，返回到，它的行为也很有趣，您必须使用其中两个：

SQL> set concat '#'
SQL> select '&goo#' from dual;
old   1: select '&goo#' from dual
new   1: select 'mygoo' from dual

'MYGO
-----
mygoo

SQL> select '&goo##' from dual;
old   1: select '&goo##' from dual
new   1: select 'mygoo#' from dual

'MYGOO
------
mygoo#

SQL>

---

最好的做法可能是始终以一个字母结尾替换变量。为了避免这种混乱。

SQL> set concat '.'
SQL> select '&goo.' from dual;
old   1: select '&goo.' from dual
new   1: select 'mygoo' from dual

'MYGO
-----
mygoo

SQL> select '&goo..' from dual;
old   1: select '&goo..' from dual
new   1: select 'mygoo.' from dual

'MYGOO
------
mygoo.

SQL> set concat '#'
SQL> select '&goo#' from dual;
old   1: select '&goo#' from dual
new   1: select 'mygoo' from dual

'MYGO
-----
mygoo

SQL> select '&goo##' from dual;
old   1: select '&goo##' from dual
new   1: select 'mygoo#' from dual

'MYGOO
------
mygoo#

SQL>