Just ORACLE_HOME

ORACLE_HOME environment is important;
So,

1. ORACLE_HOME=/u01/oracle/product/10.2.0/db
2. ORACLE_HOME=/u01/oracle/product/10.2.0/db/

Both choices (1 and 2) difference or not?


$ export ORACLE_SID=oradb
$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db
$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Fri Oct 24 18:02:38 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area 419430400 bytes
Fixed Size 2084392 bytes
Variable Size 121635288 bytes
Database Buffers 289406976 bytes
Redo Buffers 6303744 bytes
Database mounted.
Database opened.
SQL>

$ sysresv

IPC Resources for ORACLE_SID "oradb" :
Shared Memory:
ID KEY
2326528 0x8108a6d0
Semaphores:
ID KEY
2588673 0xc9943b44
Oracle Instance alive for sid "oradb"


$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db/

$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Fri Oct 24 18:03:17 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.

Connected to an idle instance.

$ sysresv

IPC Resources for ORACLE_SID "oradb" :
Shared Memory
ID KEY
No shared memory segments used
Semaphores:
ID KEY
No semaphore resources used
Oracle Instance not alive for sid "oradb"

"Can not connect database"

$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db

$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Fri Oct 24 18:03:35 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.


Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.



$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db/
$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Fri Oct 24 18:07:30 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area 419430400 bytes
Fixed Size 2084392 bytes
Variable Size 121635288 bytes
Database Buffers 289406976 bytes
Redo Buffers 6303744 bytes
Database mounted.
Database opened.

$ sysresv

IPC Resources for ORACLE_SID "oradb" :
Shared Memory:
ID KEY
2326528 0x8108a6d0
Semaphores:
ID KEY
2588673 0xc9943b44
Oracle Instance alive for sid "oradb"



$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db

$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Fri Oct 24 18:08:49 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.

Connected to an idle instance.


$ sysresv

IPC Resources for ORACLE_SID "oradb" :
Shared Memory
ID KEY
No shared memory segments used
Semaphores:
ID KEY
No semaphore resources used
Oracle Instance not alive for sid "oradb"

"Can not connect database"

$ export ORACLE_HOME=/u01/oracle/product/10.2.0/db/

$ sysresv

IPC Resources for ORACLE_SID "oradb" :
Shared Memory:
ID KEY
2293760 0x0d8f4c98
Semaphores:
ID KEY
2392065 0xc0d83e84
Oracle Instance alive for sid "oradb"


>>>
That mean "/" make different about Oracle(ORACLE_HOME);
It'll affect when we use some program on local (oracle program) and connect to database on local.
And I think many people have used ORACLE_HOME=/u01/oracle/product/10.2.0/db
>>>