SQL * Plus可以从机器读取环境变量是否正在运行？ [英] Can SQL*Plus read environment variables from the machine is it running on?

问题描述

我知道数据库引擎本身（通常）在另一台机器上，SQL * Plus没有直接的方式来阅读这些环境变量，但我处于一个棘手的情况，我只需要客户端本身运行的机器上的环境变量。

有没有办法从单个脚本中将这些值作为这些值从SQL * Plus客户端中进行欺骗那将在SQL * Plus中运行？脚本由单个开始/结束的PL / SQL块组成，但是如果我需要使用set / define / variable sort的SQL * Plus指令，也不应该是问题。

我不能做的是改变SQL * Plus可执行文件本身的启动方式（我没有访问权限作为参数传递值）。

有没有办法完成这个？

注意： dbms_system.get_env（）从服务器本身检索环境变量，这是我不想要的。

解决方案

你可以得到一些客户端相关来自 USERENV context ，但不是任意的环境变量。

如果您可以在本地计算机上创建一个文件，您可以使用 主机命令根据环境变量设置替换变量：

  SQL> ;主机echo定义homedir = $ HOME> /tmp/gethome.sql 
 
 SQL> @ / tmp / gethome.sql 
 SQL>主机rm -f /tmp/gethome.sql 
 
 SQL>选择'& homedir。'作为双重居所; 
 
 HOME 
 ------------ 
 / home / apoole 
 
 1行选择。 
  

不是很漂亮，但如果不能将命令行上的变量作为位置参数传递，你的选择是相当有限的。

这当然是使用Unix-y路径和命令，但是你可以在Windows中做同样的事情。

I'm aware that the database engine itself is (often) on another machine and that SQL*Plus has no direct way of reading those environment variables, but I'm in a tricky situation where I merely need the environment variables from the machine the client itself is running on.

Is there a way to cheat these values into the SQL*Plus client from within a single script that will be run in SQL*Plus? The script consists of a single begin/end PL/SQL block, but if I need to use SQL*Plus directives of the set/define/variable sort that shouldn't be a problem either.

What I can't do is alter the way that the SQL*Plus executable itself is started (I don't have access to pass the values in as arguments).

Is there any way to accomplish this?

Note: dbms_system.get_env() seems to retrieve environment variables from the server itself, which is what I do not want.

解决方案

You can get a few client-related things from the USERENV context, but not arbitrary environment variables.

If you can create a file on your local machine you could use the host command to set a substitution variable based on an environment variable:

SQL > host echo define homedir=$HOME > /tmp/gethome.sql

SQL > @/tmp/gethome.sql
SQL > host rm -f /tmp/gethome.sql

SQL > select '&homedir.' as home from dual;

HOME
------------
/home/apoole

1 row selected.

Not very pretty, but if you can't pass the variables on the command line as positional parameters then your options are rather limited.

This is using a Unix-y paths and commands of course, but you can do the same sort of thing in Windows.

这篇关于SQL * Plus可以从机器读取环境变量是否正在运行？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！