Apr 26, 2011

Oracle Database XE 11g beta

Last week Oracle announced database XE 11g beta:

The beta edition supports only two operating systems:

So what about using the Linux x64 edition?
But first: You should consider the following licensing restrictions (see here):
  • Only one CPU will be used.
  • Only one installation on a single computer allowed.
  • The maximum amount of user data in an Oracle Database XE database cannot exceed 11 gigabytes.
  • The maximum amount of RAM that an Oracle Database XE database uses cannot exceed 1 gigabyte
  • HTTPS is not supported natively.
The installation itself is straight forward:
  1. Log on to your computer with root permissions.
  2. Go to the following Web site:


  3. Click Free Download and follow the instructions to select and download the Linux version of Oracle Database XE.
  4. Run the Oracle Database XE executable oracle-xe-11.2.0-0.4.x86_64.rpm to install Oracle Database XE.
    $ rpm -ivh downloads/oracle-xe-11.2.0-0.4.x86_64.rpm

    The installation displays a status of its progress.

  5. When prompted, run the following command:
    $ /etc/init.d/oracle-xe configure
  6. Enter the following configuration information:
    • A valid HTTP port for the Oracle APEX (the default is 8080)
    • A valid port for the Oracle database listener (the default is 1521)
    • A password for the SYS and SYSTEM administrative user accounts
    • Whether you want the database to start automatically when the computer starts
      If you enter Yes, then the database starts immediately

That's it.

Apr 2, 2011

Linux Shell Programming: Converting hex to binary

What about:
  • You have to convert a hex value into a binary value
  • Your only tool is a linux shell
  • You have to start in 30s
  • You have to do it for >10000 hex values
Write a small program in c or java or whatever you would prefer?

What about this:
schroff@hades:$ echo "ibase=16;obase=2; 10 "|bc
schroff@hades:$ echo "ibase=16;obase=2; 1F "|bc
ibase: base of input value
obase: base of output value
The following bases can be used:
  • 16 -> hex
  • 10 -> decimal
  •  8 -> octal
  •  2 -> binary