Create a simple test database into a single filesystem

Add the entry into the oratab

cat /etc/oratab
BDTDB:/btrfs/u01/product/12.1.0/dbhome_1:Y

oraenv on this entry

[oracle@lxc ~]$ . oraenv
ORACLE_SID = [oracle] ? BDTDB
The Oracle base has been set to /btrfs/u01

Create a simple init file:

[oracle@lxc ~]$ cat $ORACLE_HOME/dbs/initBDTDB.ora
db_name=BDTDB
memory_target=1500m
processes = 150
audit_trail =none
db_block_size=8192
db_domain='local'
db_recovery_file_dest=/btrfs/databases/oradata/flash_recovery_area
db_recovery_file_dest_size=2G
diagnostic_dest=/btrfs/databases/oradata/diag
open_cursors=300
remote_login_passwordfile=EXCLUSIVE
undo_tablespace=UNDO
compatible ='12.1.0'
DB_CREATE_FILE_DEST=/btrfs/databases/oradata
DB_CREATE_ONLINE_LOG_DEST_1='/btrfs/databases/oradata'
control_files = (/btrfs/databases/oradata/BDTDB/controlfile/control1.ctl)

Create the needed directories:

[oracle@lxc ~]$ mkdir /btrfs/databases/oradata
[oracle@lxc ~]$ mkdir /btrfs/databases/oradata/BDTDB
[oracle@lxc ~]$ mkdir /btrfs/databases/oradata/BDTDB/controlfile
[oracle@lxc ~]$ mkdir /btrfs/databases/oradata/flash_recovery_area
[oracle@lxc ~]$ mkdir /btrfs/databases/oradata/diag

Launch the database creation:

Copyright (c) 1982, 2013, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup nomount
ORACLE instance started.

Total System Global Area 1570009088 bytes
Fixed Size                  2288776 bytes
Variable Size             905970552 bytes
Database Buffers          654311424 bytes
Redo Buffers                7438336 bytes
SQL> CREATE DATABASE BDTDB UNDO TABLESPACE UNDO;

Database created.

SQL> @?/rdbms/admin/catalog.sql
SQL> @?/rdbms/admin/catproc.sql