Sunday, April 22, 2007

Synchronising two directory trees - update

I've just released an update to tree-sync-2.2.pl on CPAN. This fixes a few bugs with special character handling in filenames.

I've currently three main uses for the script:
  • On my Windows XP laptop, I use it to backup my working files to an external drive. For this I use the "fwdonly" mode so that the external drive copy is a perfect copy of what I have on the laptop.
  • Also on my laptop, I have a collection of files that I sync with the external drive in "full" sync mode (default). This means changes will be exchanged bidirectionally. This is useful because sometimes I will drop files into this area with the external drive connected to another machine.
  • Thirdly, I use it on my server to sync a collection of files from cvs into a web-visible area.


PS: As of Oct-2008, the tree-sync project is now on github. Use this if you want to contribute to development. Of course, releases will still be distributed for use on CPAN.

Find and tail the Oracle alert log

"Where's the alert log?" .. usually the first thing you want to know when looking at a new database.

Oracle's Grid Control solves this problem very well with it's web interface. But not always available.

Or in my case recently, where I had 6 databases setup on a single machine for various testing scenarios, I was getting tired of cd'ing all over the place, forgetting paths, or ending up with too many windows open for my own good. Getting well sick of this, I did a quick hunt for scripts to help but surprisingly didn't find much. So diving in, I created oraAlertLog.sh and now I'm happy;)

This script is for running on the database server. The Oracle environment must be set, and - at least for the first call - the database must be available so that the "background_dump_dest" parameter can be obtained. The script will cache the alert log location so that it will still work if the database happens to be down.

After getting this running I thought "duh!", should have been in perl so it would be possible to run on any platform supported by Oracle. Here's a version in Perl: oraAlertLog.pl. It requires Perl with DBI and DBD::Oracle .. the Perl distribution included with Oracle Database is fine for this (you just need to make sure the environment is properly configured).