Primary key field type

[slobodan]

Is there more efficient field type for UUID primary key then varchar(25), for nuBuilder 4.5 and MariaDB database?

[kev1n]

What do you mean by more efficient/what do you want to achieve? You can use an auto increment pk but do not use it with subforms.

[slobodan]

I am starting development of new project in PowerDesigner for nuBuilder and MariaDb. Since it is better to make careful selection of possible solutions during the project design, rather then in the coding phase, I am considering data types for primary keys.
Subforms are limited to 1000 rows, by design, so speed and size may be insignificant feature in those circumstances. On the other hand, a subform can work with a much larger tables, if the number of records is limited by sql, then even this statement does not stand. While researching on the Internet, I came across recommendations that the mysql primary key should never be kept in varchar fields. In this moment I have not any special demand in focus, just attempting to define general guidelines for the project.