What you described this sounds like the most appropriate:
CREATE TABLE user_file (
user_id uuid,
modified_date timestamp,
file_id timeuuid,
PRIMARY KEY(user_id, modified_date)
);
If you normally need more information about the file then either store that as
additional fields or pack the data using something like JSON or Protobuf.
> my return list may still not accurate because a single directory could have
> lot of modification changes. I basically end up pulling out series of
> modification timestamp for the same directory.
Not sure I understand the problem.
Cheers
-----------------
Aaron Morton
Freelance Cassandra Consultant
New Zealand
@aaronmorton
http://www.thelastpickle.com
On 10/07/2013, at 6:51 PM, Jimmy Lin <y2klyf+w...@gmail.com> wrote:
> I have an application that need to find out the n most recent modified files
> for a given user id. I started out few tables but still couldn't get what i
> want, I hope someone get point to some right direction...
>
> See my tables below.
>
> #1 won't work, because file_id's timeuuid contains creation time, not the
> modification time.
>
> #2 won't work, because i can't order by a non primary key
> column(modified_date)
> #3,#4 although i can now get a time series of modification time of each file
> belongs to a user, my return list may still not accurate because a single
> directory could have lot of modification changes. I basically end up pulling
> out series of modification timestamp for the same directory.
>
> Any suggestion?
>
> Thanks
>
>
>
> #1
>
> CREATE TABLE user_file (
>
> user_id uuid,
>
> file_id timeuuid,
>
> PRIMARY KEY(user_id, file_id)
>
> );
>
>
>
> #2
>
> CREATE TABLE user_file (
>
> user_id uuid,
>
> file_id timeuuid,
>
> modified_date timestamp,
>
> PRIMARY KEY(user_id, file_id)
>
> );
>
>
>
> #3
>
> CREATE TABLE user_file (
>
> user_id uuid,
>
> file_id timeuuid,
>
> modified_date timestamp,
>
> PRIMARY KEY(user_id, file_id, modified_date)
>
> );
>
>
>
> #4
>
> CREATE TABLE user_file (
>
> user_id uuid,
>
> modified_date timestamp,
>
> file_id timeuuid,
>
> PRIMARY KEY(user_id, modified_date, file_id)
>
> );
>
>
>
>
>
