Hi there.
The things I wanna to talk about today are - relational databases building. Particularly I would discuss such the attainments of relational sql as join and subselect. For my experiment I'll take PostgreSQL and Python.
So, lets start:
BASH:
user@host~$ su postgres
postgres@host~$ createuser -P test
Enter password for new role:
Enter it again:
Shall the new role be a superuser? (y/n) n
Shall the new role be allowed to create more new roles? (y/n) n
postgres@host~$ createdb test
postgres@host~$ exit