oracle - Oracle NLS 设置中的 session 与实例与数据库

Question

为什么在 Oracle 中有 三 逻辑 独特 的意见电话 国际 L 语言小号 支持？

我可以理解需要区分 session 和数据库 - 允许客户端自定义设置。

Session 与 Instance 呢？

我运行了一个查询来比较它们之间的值，这是结果(我注意到 NLS_DATABASE_SETTINGS 有更多的参数，其他的所有参数加上更多，因此我正在用它做一个外连接作为我的起点):

SELECT
   db.parameter as parameter,
   db.value as database_value,
   s.value as session_value,
   i.value as instance_value
FROM
   nls_database_parameters db
LEFT JOIN 
   nls_session_parameters s
ON s.parameter = db.parameter
LEFT JOIN 
   nls_instance_parameters i
ON i.parameter = db.parameter
ORDER BY parameter

我正在尝试深入挖掘并解决我的 pl/sql 开发人员客户端的问题，单独无法显示希伯来语字符。公司里的其他人都是。

更新 :按照我发布的解决方案 here 解决了希伯来语中显示字符的问题(这不是这里的问题) .

Answer 1

好问题，直到我做了一些研究，我才知道它们之间的区别。看看这个网站 National-Language-Support

NLS_DATABASE_PARAMETERS

When you create your database, you tell it how you are going to handle or not handle globalization of the database. The NLS_DATABASE_PARAMETERS view will display what these settings were at database creation time. These are fixed at the database level and cannot be changed. The good thing is that while they do set up some of your options down the road with regard to having your database talk globally, they are only used when check constraints are enforced in the database. Therefore, you will not really need to worry about what these settings are after database creation time.

NLS_INSTANCE_PARAMETERS

As you know, you can change a variety of parameters for your instance through either the INIT.ORA file or the SPFILE. The NLS_INSTANCE_PARAMETERS view will display those settings that are set at the instance level.

NLS_SESSION_PARAMETERS

In addition, you have the ability to set each individual session's globalization parameters and the NLS_SESSION_PARAMETERS view will show you what the current settings are. This view is specific to the session querying from it.