"Perceived need" is better diff detection, i.e., obviate false diff detection just because, for exaple, a permission for a different user comes before the permission now marked as a diff but happens to be present in both old and new.

@Stephen - Are you hoping to just use the external diffing tool to view the differences, or are you expecting this to support more complex operations such as merges?

Whichever is the best one you could include from what appears to be a decent list at http://stackoverflow.com/questions/792910/best-graphical-source-code-diff-viewer-editor-for-code-comparison-and-merging

The one I used to use is no longer available as it was within a CASE Tool - very smart and configurable.

I've used the add-on within Notepad++ and it's OK, but still doesn't scan far enough for my liking with SQL scripts. Having a hook to start up Notepad++ with the 2 SQL files would be a start for me as I can at least adjust for spaces, parens, etc and get to the real meat of the differences.

I have Active File Compare, but it can be buggy although when working it does a good job, but isn't SQL-versant, sadly.

Wikipedia has a big comparison page, too, for file diff software.

I guess "hooks to the most popular" would be a good starting point (including Notepad++ of course).

Thanks for asking.

Out of interest, which external diff viewers would you want to use?

This would be helpful as, all too frequently, the built-in diff viewer shows diffs that, if it had looked a little further, like humans do, would not have exhibited a diff. Some diff viewers/detectors give options as to how many lines to scan before a diff is exhibited - this, too, would be valuable as a configurable option.