Is the ID field returned from 'account/verify_credentials' unique for each user and can it change?

[trance_32]

I’m creating a ‘sign in with Twitter’ app for my website, and I’m at the point where I need to save a user to a database.
To be able to identify a user when he next logs in I obviously need to set data in the table which is unique to each user and can’t change.

Although I will request a users email address; I understand a user can register on Twitter without an email address (phone number instead), so I want to avoid using this to log a user into my site.

I know I could just use OAUTH tokens but it would mean adding more columns to my site which I would prefer to avoid.

So my question is can I use an ID from the ‘account/verify_credentials’ object to identify a specific user??
And also can this ID field change at any time??

Thanks

[andypiper]

The id value in the user object returned in verify_credentials is unique and static for every user. The screen_name may change, but the ID value will not.

[trance_32]

Thanks