Assume that I have a regular version, would it be possible to create 2 databases?If "regular version" means a different Edition (for example Standard or Enterprise), then you can create as many databases as you want. How many of them can run simultaneously will depend on your machine.
If global_names = TRUE then the full database name is <db_name>.<db_domain> and that makes a difference for connecting to remote databases. But that is a whole separate topic.
$ sqlplus /nolog connect system ... password ... Connected. show parameter db_name ... show parameter db_domain ... show parameter db_unique_name ... show parameter service_name ... show parameter global_name .... TRUE|FALSE select * from global_name; ... select name from v$database; ... select instance_name from v$instance;
if I want to know what my created database name is, what should I do? Specially, where should I type the command for that? In MS-DOS or in sql*plus?Depends... if you are already connected, clcarter has already answered. Different situation if you are not connected, and you don't know database name(s).
C:\>sc queryex type= service state= all | find "OracleService" | find "SERVICE_NAME"
Assume that I have a regular version, would it be possible to create 2 databases? Of course, with instance for each of the database.The answer would be "no" if you are still referring to the XE instance. XE License terms don't allow to have more than one instance on each server.