Tag Archives: shell

Execution of Oracle SQL commands from within UNIX or LINUX shell scripts:

In the management of Oracle RDBMS, we frequently have the need to develop shell scripts to manage our databases. This article demonstrates the use of BASH shell script to connect to an Oracle database and execute PL/SQL and SQL statements from within the Oracle database. The following procedure will work on UNIX and LINUX machines.

1. Logon to your Oracle database server as the Oracle software owner.

2. Use vi to create a new file with the name sql_shell_test.sh

mylinux:> vi sql_shell_test.sh
“sql_shell_test.sh” [New file]

~
~

3. Press the ‘a’ key once (for append operations) and past the following text into your file.

sqlplus ‘/ as sysdba’ <

4. Press the keys : –> w –> q and hit the return key to save and exit vi.

5. Execute the chmod command to change you file status to read_write_execute for owner and group

mylinux:> chmod 770 sql_shell_test.sh
mylinux:>

6. As the Oracle software owner, execute the shell script sql_shell_test.sh with the following command.

mylinux:>./sql_shell_test.sh

7. Perform an ls command and you can see that the script has generated the output file test_shell_script_output.lst.

mylinux:>ls -lrt
-rwxrwxrwx 1 oracle dba 148 May 13 03:30 sql_shell_test.sql
-rw-r–r– 1 oracle dba 1391 May 13 03:32 test_shell_script_output.lst
mylinux:>

8. Perform a cat command to see the output of file test_shell_script_output.lst.

mylinux:>cat test_shell_script_output.lst
SQL> select * from v$instance;

INSTANCE_NUMBER INSTANCE_NAME
————— —————-
HOST_NAME
—————————————————————-
VERSION STARTUP_T STATUS PAR THREAD# ARCHIVE LOG_SWITCH_WAIT
—————– ——— ———— — ———- ——- —————
LOGINS SHU DATABASE_STATUS INSTANCE_ROLE ACTIVE_ST BLO
———- — —————– —————— ——— —
1 orcl
frankie
10.2.0.4.0 13-MAY-10 OPEN NO 1 STOPPED
ALLOWED NO ACTIVE PRIMARY_INSTANCE NORMAL NO

SQL> select name, open_mode from v$database;

NAME OPEN_MODE
——— ———-
ORCL READ WRITE

SQL> spool off
mylinux:>

This concludes the execution of Oracle SQL commands from within UNIX or LINUX shell scripts.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

Shell script to remove trace or log files from ORACLE environment.

The Oracle RDBMS produces a significant number of trace and log files, which record current status and other information related to the condition of the database system. Part of the administration of an ORACLE RDBMS is to remove these files from the OS layer once they become obsolete. This article covers the creation of shell script to remove such files from the Oracle database server in a UNIX or LINUX environment.

1. Logon to your Oracle database server as the Oracle software owner.

2. Logon to SQLPLUS with SYSDBA privileges.


mylinux:> sqlplus ‘/ as sysdba’

SQL*Plus: Release 10.2.0.4.0 – Production on Tue Dec 15 18:08:39 2009

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>

3. Use the SQLPLUS command show to see the location of your
background_dump_dest directory.


SQL> show parameter background_dump_dest

NAME TYPE VALUE
———————————— ———– ——————–
background_dump_dest string /orcl/admin/orcl/bdump
SQL>

4. Exit out of SQLPLUS.


SQL> exit
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 –
64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
mylinux:>

5. Change directories to the location of you back


mylinux:> cd /orcl/admin/orcl/bdump
mylinux:>

6. Execute the following statement to see how many trace files exist greater than 3 days old.


find . -name “*trc” -mtime +3 -exec ls -lrt {} \;

mylinux:> find . -name “*trc” -mtime +3 -exec ls -lrt {} \;



-rw-r—– 1 oracle dba 943 Jul 12 13:00
./orcl_m001_11864.trc
-rw-r—– 1 oracle dba 811 Jul 12 23:00
./orcl_m001_17140.trc
-rw-r—– 1 oracle dba 897 Jul 13 13:00
./orcl_m001_7152.trc
-rw-r—– 1 oracle dba 789 Jul 13 23:00
./orcl_m001_29058.trc
mylinux:>

7. Execute the following command to remove all file which are older than 3 days: find . -name “*trc” -mtime +3 -exec rm {} \;

mylinux:> find . -name “*trc” -mtime +3 -exec rm {} \;
mylinux:>

8. This shell command can be placed in an executable shell script and executed through CRON to automatically delete files older then three days. Note: The example below will remove trace files from your current directory ending in trc. You will have to replace the find “.” with find “directory_structure” to remove files in a specific directory.

Example: You wish to remove all files older then 3 days in directory
/opt/oracle/db_1/bdump the command would be.


find /opt/oracle/db_1/bdump -name “*trc” -mtime +3 -exec rm {} \;

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

Shell script to perform string replacement in multiple files for UNIX and LINUX:

As a DBA, regardless of RDBMS type, you will come across the need to replace text strings in dozens if not hundreds of files to facilitate the completion of your job. In this article we will cover the use of bash and perl scripts to perform text replacement of multiple files within a UNIX or LINUX environment.

1. Logon to your UNIX or LINUX server as the owner of the files you want to update or a user which has permission to update these files.

2. In this procedure we will create a file named files.txt containing a listing of all files we wish to update.

mylinux:> more files.txt
./test1.txt
./test2.txt
./test3.txt
./test4.txt

3. Next create a file called update.sh with the following text.

dt=`date “+%m%d%Y”` # Gets current date.
cat ./files.txt|while read line # Reads in all files from files.txt one line at a time.
do # Opens a loop
cp $line $line$dt # copies original file to backup with file_name+date.
ls $line |xargs perl -pi -e ‘s/{old_string}/{new_string}/g’ # if found replace old_string with new_stirng
done # ends loop

4. Change permissions on the update.sh to 770, so it will execute.

mylinx:>:>chmod 770 update.sh
mylinx:>:>

5. View the contents of one of the files in you files.txt file.

mylinx:>:>cat test*
one
one
one
one
mylinx:>:>

6. In this example, all of the files contain the text “one” which we will replace with the string “two”. Thus your update.sh file will look like the example below.

dt=`date “+%m%d%Y”`
cat ./files.txt|while read line
do
cp $line $line$dt
ls $line |xargs perl -pi -e ‘s/one/two/g’
done

7. Execute the update.sh file with the command: ./update.sh.

mylinx:>:>./update.sh
mylinx:>:>

8. Now cat all files named test*

mylinx:>:>cat test*
two
two
two
two
mylinx:>

As you can see all strings of “one” have been replaced with the string “two”. This completes replacement of strings in UNIX and LINUX.

Larry Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

UNIX CRON – Shell script errors with [10]: sqlplus: not found

In normal administration of an Oracle RDBMS on UNIX or LINUX operating systems, the DBA will be required to develop shell and SQL scripts to maintain his/her RDBMS. In fact, to be considered a mid to senior DBA you will need to be well versed in scripting at the OS layer. In this article we will review a common error which occurs in a shell script called by CRON due to a lack of properly set variables.

1. In a normal scenario, the DBA has developed a shell script which calls and executes a SQL script to perform a certain maintenance task. In testing, the DBA executes the script as the oracle software owner and the script performs perfectly. However, when placed in the OS CRON for execution, the following error occurs.

[10]: sqlplus: not found

2. The error occurs because the environmental variables are not being read. Thus, the OS does not know where to find the executable: sqlplus.

3. The solution is to update your shell script and hard code the directory structure for the command sqlplus. An example would be if sqlplus is located in the following path /u01/opt/app/oracle/bin then perform the following:

Replace:

sqlplus

With:

/u01/opt/app/oracle/bin/sqlplus

This completes resolving the error message [10]: sqlplus: not found in a shell script called through CRON.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com