As I was on holiday in Toulouse (France), I'll have to skip a week or two of my OTN Forms forum posts. However, while cleaning up my browser bookmarks, I found some gems of the SQL and PL/SQL forum I thought I'd share. Last year, user "cd" wrote an excellent introduction on using regular expressions in the Oracle 10g database. You can find the series here:
If you haven't got a clue about what regular expressions are, make the effort of trying out the examples, you'll find they are very powerful and can make your programming life a lot easier. If you prefer your reading material to be portable, you could try the Oracle Regular Expressions Pocket Reference by Jonathan Gennick.