This came in the Python groups, and I put one up in the database group, since I will later have to use Python to access the SQL file, so therefore tackling one thing at a time. Also, there were no answers that were coming up in the .database group.
On top of that: > Really? You can have ships in the Outcomes relation that DO NOT >APPEAR in the Ships relation... Goodbye referential integrity. > > Besides which, if they don't appear in the Ships relation, then >there is NO INFORMATION to tell you what ship CLASS it is a member of -- >do you group them all as "UNKNOWN" class, or do you declare each to be >the only ship of its class (and thereby use the ship name as the class >name)? This meant that some ships weren't listed in the Ship table provided but did show up in the Outcome. Therefore, they are not directly referenced one to the other. > <sigh> Another gmail user found only by back referencing responses... What is meant by this statement? So in short of the responses given, I need to study further: GROUP BY, HAVING, AS, COUNT, and subselect queries, right? The relational algebra, I am able to translate it into SQL, or most of it, meaning turning it into the queries of SQL. This is not an advanced database course, but more a basic intro to database systems. -- http://mail.python.org/mailman/listinfo/python-list