Ok, If I go with number 1, I'm not sure how can I denormalize it to
print the CD titles...
If I can't join on the CD titles them selves... How can I fetch the
names of the CDs if the select is
SELECT * FROM Ownership WHERE user_id = user_id ?
Bill, 10x a lot for your help...
On Jan 17, 10:13
By denormalize, I mean storing the CD titles in the Ownership entities
as well. Yep, there'll be duplication to avoid the join, but you'll
be able to get the CD titles from the fetched Ownership entities in
one query.
I'm still trying to figure out best practices myself with the
datastore.
Chen,
Some differences between using an Ownership model and using a list of
references to CDs in a User entity:
1) You can store info associated with Ownership as mentioned in my
previous message. So if you want to print all the CD titles owned by
a user, you could denormalize CD titles and
You could do an entity that has 50 genre counters.
Some thoughts:
1) It seems like you can make genre part of a list property in a CD
since each CD will only be a small number of genres.
2) I wouldn't use a Reference List for a User entity, because a User
might have thousands of CDs. See Rafe
Hi,
I'm not sure I've followed you with whole Ownership model..
Isn't that a RDBMS approach to the data and not BigTable's?
Regarding the genres, they are fixed (53 to be exact) and he can't
select new genres that aren't in the predefined list.
Regarding the counter entity, this is basically
I'm not sure I've followed you with whole Ownership model..
Isn't that a RDBMS approach to the data and not BigTable's?
The two approaches aren't mutually exclusive. In the case of User -
CD, a User can have thousands or more CDs and a CD could be purchased
by millions. Under those
Bill if I use an ownership model,
How do you fetch all the cds of a user?
you select on Ownership, then get the tuples with user id / cd id
Now you need to fetch many cd id from the CD entity..
So what's the difference?
If you store them as a list of IDs in the User, you still have to go
over the
