Conventions for Database Names 
You define the database name when you create the database. The database system automatically converts all lower-case letters you enter into upper-case letters.
Note that you cannot change the database name later.
General Restrictions
The database name can have a maximum of eight characters.
It may only contain characters from the 7-bit ASCII character set.
It must not begin with an underscore or a period.
Additional Restrictions on Microsoft Windows
The database name must not contain any of the following characters:
\ / : * ? " < > |
The following database names are not allowed:
CON, PRN, AUX, NUL
COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9
LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9
The database name must not end with a period.
When you are planning a database port from Unix or Linux to Microsoft Windows, observe the restrictions listed above.