This chapter is from the book
What to Do If Database Creation Fails
Database creation fails if there are syntax errors in the SQL for the CREATE DATABASE script, if files that you are trying to create already exist, or if there are operating system errors such as inadequate directory permissions or not enough space in the file system.
If any of these problems occur, you need to delete any files that may have been created (with the exception of the control files if the REUSE statement is used), make alterations to the CREATE DATABASE statement as needed (correcting any errors), and attempt the creation again.