> 1. I tend to think URL as a part of the user interface. If the user > look at (usually simple and structured in rails application) URL, > wouldn't she be confused by the seemingly random and very large > number assigned to her reply post? Topic's id #87 corresponds to the > 87th-ness nature of the topic posted in the forum. Reply id #3 would > correspond to the 3rd-ness nature of the reply to the given topic, > reply id #1074 would not. I know, I know, I might sound like someone > who is suffering ocd.. ;)
Rick's reply covers that, use routes. Additionally, you may want to consider adding another 'index' column rather than using the IDs like that. > 2. This one is a bit more practical issue. Let's say I'm building a > public forum hosting service. (It is indeed something I have in > mind.) At some point, my site hosts 10,000 forums, each having its > own forum_id. Let's say each forum has average of 10,000 topics, > each having its own topic_id. And each topic has average of 100 > replies, each having its own reply_id. If I have to use a flat > integer id space, there will be replies with id like #10,000,000,000. > (10,000 * 10,000 * 100) Now, 32-bit unsigned integer can't handle it > since its max value would 4,294,967,295. I could just use 64-bit > unsigned integer, I guess, but it does take more spaces and what if > my site becomes even more successful to the extent even 64-bit > integer will max out? If you're storing forum posts, you're looking at a lot of data, like say, 1k per row. If you've maxed out a 64 bit integer, you've got exabytes - yottabytes of storage. No one has that much storage, Not google, or high end scientific supercomputers. You'll be fine. > In some ways, id's are like memory addresses, but no user ever get to > see the memory address values.. Are there other reasons against the > use of multiple integer column id's other than the fact that > ActiveRecord doesn't support it? Look at it another way, if you can live without it, why try to use it? -- Cheers Koz _______________________________________________ Rails-core mailing list Rails-core@lists.rubyonrails.org http://lists.rubyonrails.org/mailman/listinfo/rails-core
