SQL*Plus for Oracle

SQL*Plus may display data from tables of database in default language set in system OS. So sometimes you can see in your language strange signs. How repair it?

Go to in search or Start to the Control Panel->System. Choose Advanced System settings.
Then click Environment Variables. In the section System Variables click the New button. In the Edit System Variable (or New System Variable) window, specify the name and value for a coding language. The name is NLS_LANG. The value may be different for each language. For Polish language it is: POLISH_POLAND.EE8PC852.

List of common NLS_LANG settings used in the Command Prompt you find on this Oracle website: here
Some of them you see in the below table:

Click the OK button. Close all remaining windows by clicking OK button.
Open SQL*Plus window, connect to a database and check if data in the tables are displayed in your language.
In Command Prompt you can test value NLS_LANG variable. Write in console:
set NLS_LANG
and enter.
You see the ettings for language, using also by SQL*Plus.

The following list to help you find the Oracle character set and fit them to MS-DOS code page on your locale OS:

You fin all information about it on Oracle website.