Correct date format with notepad++ and regex

Sometimes, date formats get mixed up. I.e. if you merge databases or import values. Editing them manually may be ok, but is a lot of work whey you have many of wrong values. And errors may occur.

Editing them with a regular expression (regex) may be the easier and faster way, if you know how.

I have a merged table with imported event dates. Unfortunately, they have different formats:

2012-12-31 23:45:00

24-03-2012 21:30:00

As you can see the year and day of the second entry are different from the first entry. I need the first format.

So here are the steps:

([0-9]{2})-+([0-9]{2})-+([0-9]{4})

\3-\2-\1

$3-$2-$1

That's it.