I'm not sure why you care about this but I don't believe there's any character length restriction at application level.
At database level, you can check the "name" column of "user_model" table which I believe it's defined as type varchar.
The maximum limit of size character using character varying data type in PostgreSQL is 10485760
Yes, I am using postgreSQL only. I seen "character varying" under "name" in pgAdmin. But when i tested manually by creating user with unlimited characters, it doesnt exceeded more than 257 characters. Under naming entities also 255 is the limit mentioned in the documentation. In contrast, the database having a datatype varchar. Why?
You were correct. Naming new users like Things cannot exceed 255 characters.
I confirmed that putting 256 characters leads to a warning and cannot be saved from composer.
So the 255 length is a constraint coded at application level not a constraint from database. It's just the way how ThingWorx is designed.
I think 255 is enough length for naming a user or a Thing though. Any special reason to have a name more than 256 characters?