Category Archives: hp-ux

hp-ux, linux, unix

String replacement at UNIX or LINUX command prompt

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As an Oracle DBA you will come across many situations where you need to replace string text within OS layer files. This procedure covers the use of Perl command to perform such a task. This procedure will work in both UNIX and LINUX.

1. Logon to you Oracle server as the owner of the files you wish to perform a string replacement on.

2. We will use the command (“perl -pi -e ‘s/{old_string}/{new_string}/g’ {file_name}”) to perform our string replacement.

3. In this example we will replace all of the references to the string “MARS” with the string “EARTH” in any file that ends in test*sh, the command will appear as:

perl -pi -e ‘s/MARS/EARTH/g’ test*sh

4. List all of the contents of files of the format test*sh with the cat command.

mylinux:>cat test*sh
MARS
MARS
MARS
MARS
mylinux:>

5. Execute your perl command in the same directory where your the files are located.

mylinux:>perl -pi -e ‘s/MARS/EARTH/g’ test*sh mylinux:>

6. List all of the contents of the files with format of test*sh with the cat command.

mylinux:>cat test*sh
EARTH
EARTH
EARTH
EARTH
mylinux:>

As you can see above the test string “MARS” has been replaced with “EARTH”. This completes replacement of text string with Perl.

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

hp-ux

Setting the backspace key in HP-UX:

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The following procedure describes the setting of the backspace key in HP-UX

1. Logon to your HP-UX server.

2. While typing a command you make a mistake, but instead of backspacing the system produces ^? marks, as seen below.

myLINUX:> ls -lrt^?^?^?^?^?
ls: illegal option —
ls: illegal option —
ls: illegal option —
ls: illegal option —
ls: illegal option —
usage: ls -1ARadeCxmnlogrtucpFLbqisf [files]
myLINUX:>

3. From the command prompt type the command: stty erase ^?

myLINUX:> stty erase ^?
myLINUX:>

4. Now the backspace key is enabled for this session.

5. To automate this process, place the line command (stty erase ^?) at the end of your .profile file in you home directory. This will enable the backspace operation upon connection.

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

11g, ASM, hp-ux, itanium, linux, Oracle, Oracle 10g, oracle 9i, RAC, SQL, uncategorized, unix

Senior-Level DBA Interview Question:

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With well over a decade of Oracle experience from version 6 to 11g, I have had my share of interviewing prospective DBA employees in a range from Junior to Senior DBAs. Needless to say in this field, technical competence is the key to any new hire and early on I made the blunder of not asking the write questions during the interview. I am sure every senior person or manager has made this mistake and had to deal with either training the person from scratch or letting them go. Either of these options is not desirable in our fast past business world. So, I decided to write a couple of articles which cover what I believe a Junior, Mid, and Senior Oracle DBA should know to fill their prospective positions.

In this article we will cover what a Senior Level DBA should know to be successful. If you have any comments or questions, please email me at larry.catt@relidb.com.

Questions: NOTE: Answers here can be very broad, however they not always wrong. That is why it is important to have a proven DBA on staff or one you can call to review the answers. I have seen very inventive ways to get around the most impossible tasks and while they do not actually meet the standard way of doing the work, I would not count these people out. A person whom thinks outside of the box is very valuable in IT and believe it or not, some of the best DBA’s I have ever met thought completely outside the box, however always accomplished the task.

1. You have a brand new Solaris Machine, freshly built by the SA, with all Oracle RDBMS recommended patching and Kernel Parameters set. Please give the order of tasks to install Oracle up to its latest CPU?

2. You have just moved Oracle Binary files from an ORACLE_HOME on one server to another server. What is the oracle utility command you would use to make this new ORACLE_HOME usable?

3. Tell me why just copying the oracle datafiles from HP-UX to LINUX RHEL and starting the database would not work?

4. In what months does Oracle release CPU patches and what is the utility to apply them.

5. You need to shutdown the oracle database but it will not shutdown with SHUTDOWN IMMEDIATE. How will you shutdown the database?

6. How do you logon to Oracle server without knowing any oracle passwords?

7. How would you determine that SCATTERED READ where occuring?

8. How would you see the SQL of the currently active sessions from a command prompt?

9. When having multiple oracle homes on a single server or client what is the parameter that points all Oracle installs at one TNSNAMES.ORA file.

10. You have ASM database that used by three production systems. The server which the ASM database is shutdown. What happens to the production RDBMS?

Answers:

1. You have a brand new Solaris Machine, freshly built by the SA, with all Oracle RDBMS recommended patching and Kernel Parameters set. Please give the order of tasks to install Oracle up to its latest CPU?

– Verify that all patches are installed and kernel parameters set.(Some not all SA say the system is ready when it is not. You can save yourself a lot of problems by double checking)
– Configuration of .profile or .bash_profile for the Oracle owner.
– Base Installation of Oracle (ie what to get to 10.2.0.4 must install Oracle 10.1 first).
– Upgrade to Oracle Version Desired.
– Upgrade the database(if upgrade is necessary)
– Run UTLRP.SQL.
– Apply lastest CPU patch.
– Run UTLRP.SQL.
– Configuration of Listener.
– Configuration of client TNSNAMES.ORA file.

2. You have just moved Oracle Binary files from an ORACLE_HOME on one server to another server. What is the oracle utility command you would use to make this new ORACLE_HOME usable?

Solution:
Relink all

3. Tell me why just copying the oracle datafiles from HP-UX to LINUX RHEL and starting the database would not work?

Solution:
Differing Indian codes.

4. In what months does Oracle release CPU patches and what is the utility to apply them.

Solution:
JAN, APR, JUL, OCT

5. You need to shutdown the oracle database but it will not shutdown with SHUTDOWN IMMEDIATE. How will you shutdown the database?

Solution:
Kill the smon process.

6. How do you logon to Oracle server without knowing any oracle passwords?

Solution:
Sudo to the Oracle software owners account and logon with the command sqlplus ‘/ as sysdba’

7. How would you determine that SCATTERED READ where?
Solution:

Look in the views v$session_wait or v$session_wait_history.

Could give:

Statspack or EM report.

8. How would you see the SQL of the currently active sessions from a command prompt?

Solution:
Compare tables V$SQL view by sql_address with V$SESSION view of currently active sessions.

9. When having multiple oracle homes on a single server or client what is the parameter that points all Oracle installs at one TNSNAMES.ORA file.

Solution:
TNS_ADMIN

10. You have ASM database that used by three production systems. The server which the ASM database is shutdown. What happens to the production RDBMS?

Solution:
Other database would shutdown abort.

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

11g, hp-ux, itanium, linux, Oracle, Oracle 10g, oracle 9i, script, security, SQL, sqlplus, unix

Oracle – Use of UTL_FILE to read external OS file into Oracle RDBMS.

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Oracle – Use of UTL_FILE to read external OS file into Oracle RDBMS.

Oracle provides the procedure UTL_FILE to allow for the reading of external OS layer files from within the Oracle RDBMS. This article will give an example of how to read the contents of an external OS file and display it in the Oracle database.

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

2. Create a file called read.txt with the following text.

This is line one.

3. Logon to SQL*PLUS with an account which has DBA privileges. In this example we are using the account LJCATT.

mylinux:> sqlplus ljcatt

SQL*Plus: Release 10.2.0.4.0 – Production on Thu Jan 29 23:28:23 2009

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

Enter password:

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>

4. Create the procedure read_file as detailed below.

create or replace procedure read_file
is

v_record varchar2(50);
v_file varchar2(30) := ‘read.txt’;
v_dir varchar2(512) := ‘/home/lufsora’;
v_write utl_file.file_type;
begin

v_write:=utl_file.fopen(v_dir, v_file, ‘r’, 2000);

utl_file.get_line(v_write,v_record, v_record);

dbms_output.put_line(v_record);

utl_file.fclose(v_write);

end read_file;
/

5. Execute the procedure read_file with the command execute and the test within the OS file will be display.

SQL> execute read_file;
This is line one.

PL/SQL procedure successfully completed.

SQL>

This completes the use of UTL_FILE to read OS level files into your Oracle RDBMS.

Larry J. Catt, OCP9i, 10g
oracle@allcompute.com
www.allcompute.com

11g, hp-ux, itanium, linux, Oracle, Oracle 10g, oracle 9i, script, SQL, sqlplus, unix

Oracle – ORA-29280: invalid directory path when using UTL_FILE

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Oracle provides the package UTL_FILE to produce OS layer files from within the Oracle RDBMS. This article will describe the common error of ORA-29280 which maybe received when using the UTL_FILE procedure and how to resolve it.

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

2. Create a file called create_file.sql with the following SQL.

create or replace procedure test_file
is

v_record varchar2(50) := ‘Testing file creation’;
v_file varchar2(30) := ‘test_file.txt’;
v_dir varchar2(512) := ‘/home/lcatt’;
v_write utl_file.file_type;
begin

v_write:=utl_file.fopen(v_dir, v_file, ‘w’, 2000);

utl_file.put_line(v_write, v_record);

utl_file.fclose(v_write);

end test_file;
/

3. Enter SQL*PLUS, set ECHO and FEEDBACK to on, and execute the file
create_file.sql as a user with DBA privileges. In this example we are using the account LJCATT.

Mylinux:/home/lcatt:>sqlplus ljcatt

SQL*Plus: Release 10.2.0.4.0 – Production on Sat Jan 10 10:43:17 2009

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

Enter password:

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> set feedback on
SQL> set echo on
SQL>@./create_file.sql
SQL> create or replace procedure test_file
2 is
3
4 v_record varchar2(50) := ‘Testing file creation’;
5 v_file varchar2(30) := ‘test_file.txt’;
6 v_dir varchar2(512) := ‘/home/lcatt’;
7 v_write utl_file.file_type;
8 begin
9
10 v_write:=utl_file.fopen(v_dir, v_file, ‘w’, 2000);
11
12 utl_file.put_line(v_write, v_record);
13
14 utl_file.fclose(v_write);
15
16 end test_file;
17 /

Procedure created.

SQL>

4. Use the SQL*PLUS command show to display the initialization parameter utl_file_dir and ensure that the directory /home/lcatt is not present.

SQL> show parameter utl_file_dir

NAME TYPE VALUE
———————————— ———– ——————————
utl_file_dir string /home/lcatt/output
SQL>

5. If the directory is present, remove it with the following command:

SQL> alter system set utl_file_dir=” scope=spfile;

System altered.

SQL>

6. Logon to the database as sysdba and restart your oracle instance.

SQL> connect / as sysdba
Connected.
SQL>
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup open
ORACLE instance started.

Total System Global Area 1207959552 bytes
Fixed Size 2068728 bytes
Variable Size 654315272 bytes
Database Buffers 503316480 bytes
Redo Buffers 48259072 bytes
Database mounted.
Database opened.
SQL>

7. Now logon as the user LJCATT and execute the package test_file with the command execute.

SQL> execute test_file
BEGIN test_file; END;

*
ERROR at line 1:
ORA-29280: invalid directory path
ORA-06512: at “SYS.UTL_FILE”, line 29
ORA-06512: at “SYS.UTL_FILE”, line 448
ORA-06512: at “LJCATT.TEST_FILE”, line 10
ORA-06512: at line 1

SQL>

8. NOTE: The error produced is a result of no reference to the defined directory structure in the initialization parameter UTL_FILE_DIR. This parameter is used to allow the database access to OS layer directories. To resolve this error, connect to the database as sysdba and place the directory path in the initialization parameter UTL_FILE_DIR with the command alter system and restart the database.

SQL> connect / as sysdba
Connected.
SQL> alter system set utl_file_dir=’/home/lcatt’ scope=spfile;

System altered.

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

Total System Global Area 1207959552 bytes
Fixed Size 2068728 bytes
Variable Size 654315272 bytes
Database Buffers 503316480 bytes
Redo Buffers 48259072 bytes
Database mounted.
Database opened.
SQL> show parameter utl_file_dir

NAME TYPE VALUE
———————————— ———– ——————————

utl_file_dir string /home/lcatt

9. Connect back to the database as the user LJCATT and re-execute the procedure test_file.

SQL> connect ljcatt
Enter password:
Connected.
SQL> execute test_file

PL/SQL procedure successfully completed.

SQL>

10. Exit out of SQL*PLUS, change directories to the location of your output file, and perform an ls command to display the file generated.

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:/home/lcatt:>cd /home/lcatt
Mylinux:/home/lcatt:>ls testfile
testfile
Mylinux:/home/lcatt:>

The file was produced under the directory defined by the initialization parameter utl_file_dir and the error ORA-29280 has been resolved.

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

11g, hp-ux, itanium, linux, script, SQL, sqlplus, unix

Creating an external file from within the Oracle RDBMS.

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Oracle provides the package UTL_FILE to produce OS layer files from within the Oracle RDBMS. This article will show a basic procedure for the producing an OS layer file from within the Oracle RDBMS.

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

2. Create a file called create_file.sql with the following SQL.

create or replace procedure test_file
is

v_record varchar2(50) := ‘Testing file creation’;
v_file varchar2(30) := ‘test_file.txt’;
v_dir varchar2(512) := ‘/home/lcatt’;
v_write utl_file.file_type;
begin

v_write:=utl_file.fopen(v_dir, v_file, ‘w’, 2000);

utl_file.put_line(v_write, v_record);

utl_file.fclose(v_write);

end test_file;
/

3. Enter SQL*PLUS, set ECHO and FEEDBACK to on, and execute the file
create_file.sql.

Mylinux:/home/lcatt:>sqlplus ljcatt

SQL*Plus: Release 10.2.0.4.0 – Production on Sat Jan 03 09:43:17 2009

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

Enter password:

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> set feedback on
SQL> set echo on
SQL>@./create_file.sql
SQL> create or replace procedure test_file
2 is
3
4 v_record varchar2(50) := ‘Testing file creation’;
5 v_file varchar2(30) := ‘test_file.txt’;
6 v_dir varchar2(512) := ‘/home/lcatt’;
7 v_write utl_file.file_type;
8 begin
9
10 v_write:=utl_file.fopen(v_dir, v_file, ‘w’, 2000);
11
12 utl_file.put_line(v_write, v_record);
13
14 utl_file.fclose(v_write);
15
16 end test_file;
17 /

Procedure created.

SQL>

4. Ensure that the system initialization parameter for utl_file_dir contains the directory to which utl_file is going to write with the command show utl_file_dir.

SQL> show parameter utl_file_dir

NAME TYPE VALUE
———————————— ———– ——————————
utl_file_dir string

SQL>

5. If it does not contain the directory, as is the case in step 4, logon to your Oracle database as sysdba and add the directory structure and bounce the database, as seen below:

SQL> connect / as sysdba
Connected.
SQL> alter system set utl_file_dir=’/home/lcatt’ scope=spfile;

System altered.

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

Total System Global Area 1207959552 bytes
Fixed Size 2068728 bytes
Variable Size 654315272 bytes
Database Buffers 503316480 bytes
Redo Buffers 48259072 bytes
Database mounted.
Database opened.
SQL> show parameter utl_file_dir

NAME TYPE VALUE
———————————— ———– ——————————

utl_file_dir string /home/lcatt

SQL>

6. Execute the newly create procedure with the SQL*PLUS command; execute test_file

SQL> execute test_file

PL/SQL procedure successfully completed.

SQL>

7. Exit out of SQL*PLUS and change directory to where you wrote your file.

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:/home/lcatt:>cd /home/lcatt
Mylinux:/home/lcatt:>

8. Execute the ls and more command on the file testfile.

Mylinux:/home/lcatt:>ls testfile
testfile
Mylinux:/home/lcatt:>more testfile
Testing file creation
Mylinux:/home/lcatt:>

This completes the creation of external OS layer file from within the Oracle RDBMS.

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

11g, hp-ux, itanium, linux, Oracle, Oracle 10g, oracle 9i, unix

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

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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