Find and replace with reordered date format in notepad++

Question

I have a file with a few thousand rows to be added to a MySQL database. There are date values in the rows which are in the dd-mm-yyyy format but I need them to be in the yyyy-mm

Answer 1

To make sure you only reorder wrong formats (in case you have mixed formats from merging databases), use this:

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

This searches for (four digits, dash, two digits, dash, two digits).

In an regex capable editor like notepad++, replace it with this:

\3-\2-\1

In a tool like libre office, you need to replace it with this:

$3-$2-$1 

Edit: I wrote a blogpost about this as it seems to be a common problem: http://bytethinker.com/blog/correct-date-format-with-notepad-and-regex