Dmitry Yemanov wrote:

> "Jim Starkey" <jas@...> wrote:
>
>>"create domain rdb$user_name varchar(128) CHARACTER SET
>>UNICODE_FSS;",
>
>
> Strictly speaking, user names are SQL identifiers and hence they should be
> CHAR(31). As Claudio has pointed out, we don't support longer user names
> anyway, neither at the system tables level nor perhaps at the code level.
> The question is whether making it consistent really breaks something. Any
> customers have user names longer than 31 characters without anything granted
> to them?
>

Leaving rdb$user_name varchar(128) is security risk. What happens in
case when VeryVeryVeryVeryVeryVeryLongUserName is granted some some
rights, and after it VeryVeryVeryVeryVeryVeryLongUserName2 is added?
Suppose it will have all this rights. That's not OK.
I suggest to restrict it to 31.