Create alias same working like menu page alias

Hello,

I want to create alias in my table same link menu alias, It should be unique in my table.

Help me please...

I have the same question.

Create a text field 'alias' and then modify it on the fly just like the core Joomla does. Make it unique by concatenating a couple of fields together, or do validation to make sure it remains unique. It can be a complex process, but looking at how Joomla does it at the core helps.

Noel's answer covers creating the field. But does anybody know what needs to be done in order to actually use that field?
I guess you need to edit the router.php, but does anyone have examples on how this should be done?
Thanks!

- EDIT - 

I just found out about the new Alias field. So I'll check how it's done!