Sunday, January 28, 2007

Dev : Variables On Shell Script

B= $A+100
echo $B

What will the next line show?
a) 200 b)100100

If you answer b, then congratulation! But is there any way of making the answer a? Yes, there is. By using the keyword 'expr', the problem is solved. But how?

In the second line, instead of B=$A+100, change it to B=`expr $A + 100`. Remember the white spaces between the '$A', '+' and '100'. We can also use it for subtraction, comparison and other useful usage as well. You can either use the unix man expr, or click here for more information.

Thursday, January 25, 2007

Dev : Installing Oracle 9i on Solaris 8

Whew... It's really a mess to install oracle in Unix machine. Lucky for me, I've found some steps online where it has reduce many white hair growing on my head.

It make me sweat when asking me to change the Solaris Kernel Parameters. After some troublesome findings, I finally manage to change the kernel parameters at /etc/system and manage to get the oracle 9i installed and database created. If not, you will always get oracle error complaining "Out Of Memory". Remember, it is the kernel parameters' fault. Not your RAM, not your SWAP (because I have increase my RAM from 512Mb to 1Gb and SWAP from 500Mb to 1.5 Gb :D ).

After installing and created a database, you need to create at least a user.
To create a user :
  1. Login SQL*Plus with sqlplus "/ as sysdba".
  2. In SQL*Plus, type sql > create user user_name identified by user_password;.
  3. Grant some access for the user.
    sql > grant connect to user_name;
    sql > grant resource to user_name;
    sql > grant create any snapshot to user_name;

After that, to access oracle from other workstation, you should start the oracle process first.

  1. In console, type cd /oracle/home/bin/.
  2. To start the oracle process, in console, type ./lsnrctl start.
  3. To start the database, in console, type ./dbstart.

And there you go! The very basic of oracle. :)

Wednesday, January 17, 2007

Dev : Swap for Solaris

How do we add extra swap space in Solaris version 5.x? For the ease of most users, follow the steps as below...

1. Log in console as root.
2. In console, type root: /usr > df -k to see the available space and the available swap by typing root: /usr > swap -l in console.
3. Locate a suitable location, create a file for swapping. Eg, to create an empty 1 Gb file call swapfile: root: /usr > mkfile 1g swapfile
4. Add the swapfile to the swap. Eg: root: /usr > swap -a /usr/swapfile (must use absolute path)
5. Edit the /etc/vfstab, add in a new line call /usr/swapfile - - swap - no - to enable the swap file at the next boot.
6. Check your swap again by by typing root: /usr > swap -l in console. You will find that there is a new swap available and you are ready to use it. :)