linux下手动删除数据库实例，直接删除相应的目录就可以了，不多说了....
1. $ORACLE_HOME/dbs/
[oracle9@frogger dbs]$ pwd
/u01/app/oracle/product/9.2.0.1/dbs
[oracle9@frogger dbs]$ rm inittest02.ora
[oracle9@frogger dbs]$ rm orapwdtest02
2. $ORACLE_BASE/oradata/SID
[oracle9@frogger oradata]$ ls
default_demo01.dbfdefault_demo99.dbfdevdb02duke1test01test01_baktest02testdktestqa
[oracle9@frogger oradata]$ ps -ef|grep smon
oracle9 7162 10 ?00:04:30 ora_smon_duke
oracle9 3313 10 ?00:02:30 ora_smon_testdk
oracle9 4386 10 Apr05 ?00:00:07 ora_smon_test01
oracle9 4620 10 Apr05 ?00:00:05 ora_smon_dvdsame
oracle91230744260 22:53 pts/300:00:00 grep smon
[oracle9@frogger oradata]$ rm -rf test02
[oracle9@frogger oradata]$ df -h
FilesystemSizeUsed Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
455G381G 51G89% /
/dev/sda199M 15M 80M16% /boot
none 1004M 0 1004M 0% /dev/shm
nfs-:/u07
455G230G202G54% /u07
[oracle9@frogger oradata]$ ls
default_demo01.dbfdefault_demo99.dbfdevdb02duke1test01test01_baktestdktestqa
3. 删除log文件
[oracle9@frogger admin]$ ls
devdb02duke1test01test02testdktestqa
[oracle9@frogger admin]$ pwd
/u01/app/oracle/admin
[oracle9@frogger admin]$ cd test02
[oracle9@frogger test02]$ ls
bdumpcdumpcreatepfileudump
[oracle9@frogger test02]$ cd ..
[oracle9@frogger admin]$ ls
devdb02duke1test01test02testdktestqa
[oracle9@frogger admin]$ rm -rf test02
[oracle9@frogger admin]$ ls
devdb02duke1test01testdktestqa
[oracle9@frogger admin]$
4. 如果是用dbca创建的实例，则还要删除/etc/oratab文件中的实例信息，就一行。 删除就ok了。
/etc/oratab 运行root.sh产生的,中每一行代表一个ORACLE 实例,不允许有相同的名字，对已经存在的数据库会提示是否升级等,安
装创建数据库的时候会去检查这个文件是否存在和并检查文件中的内容,在运行dbstart 时会检查这个文件，如果是Y就启动它，是N
就不管它。
[oracle9@frogger admin]$ cd /etc
[oracle9@frogger etc]$ more oratab
#
# This file is used by ORACLE utilities.It is created by root.sh
# and updated by the Database Configuration Assistant when creating
# a database.
# A colon, ':', is used as the field terminator.A new line terminates
# the entry.Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
# $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# The first and second fields are the system identifier and home
# directory of the database respectively.The third filed indicates
# to the dbstart utility that the database should , "Y", or should not,
# "N", be brought up at system boot time.
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
#
# *:/u01/app/oracle/product/9.2.0.1:N
*:/u01/app/oracle/product/9.2.0.1:N
duke:/u01/app/oracle/product/9.2.0.1:N
test02:/u01/app/oracle/product/9.2.0.1:N
[oracle9@frogger etc]$
