Comments for DeGizmo

Comment on Redis: Relations in a NoSQL world: Using Hashes by MeerieCah

MeerieCah — Sun, 29 Aug 2010 08:31:55 +0000

Yes, really.

Comment on Redis: Relations in a NoSQL world by Daniel

Daniel — Mon, 26 Apr 2010 22:27:01 +0000

As a quick note, on delete_user, we’re first retrieving the entire list of users to then check if the to-be-deleted user is present, which is fine for a small demo but not good in a production site. Instead, to check for the existence of the user-to-be-deleted, one can use r.sismember(“user”, username) which will return just a boolean (which is also the method the author used in authentication).

Comment on Redis’ Virtual Memory Specifications Draft by QWMichael

QWMichael — Mon, 19 Apr 2010 04:55:11 +0000

I shouldn’t be surprizing so hard at that.

Comment on Getting Started: Redis and Python by foeniz

foeniz — Mon, 05 Apr 2010 05:21:00 +0000

Wow, I have been looking into this more and more, I really like what one can do with this sort of schema.

Here’s something I messed around with, it saved my app a good 5 lines of mysqlalchemy:

r.zadd(“site:%s” % id, (r.lrange(“post:%s:comment” % id, 0, 0)), r.get(“global:%s:score” % id))

Comment on Redis: Relations in a NoSQL world: Using Hashes by Sam

Sam — Thu, 01 Apr 2010 00:29:47 +0000

Without the user set, you would have to do a keys() to find out who all the users are and perform an operation on each. Once you have a lot of users, your keys() query is going to take ages (relatively speaking).

Comment on Redis: Relations in a NoSQL world by Damian Janowski

Damian Janowski — Fri, 26 Mar 2010 23:18:41 +0000

Good intro on how to structure data on Redis.

Readers may be interested in how Ohm does it. Ohm is a Ruby library that maps objects to Redis back and forth. It supports the native Redis data types and higher level features like relationships, indexes, validations, etc.

http://ohm.keyvalue.org

Comment on Redis: Relations in a NoSQL world: Using Hashes by Adam

Adam — Thu, 25 Mar 2010 11:12:12 +0000

Got it… I’ve been trying the getting up at 5am thing recently and my night time brain isn’t as good as my morning brain now

This was written at night O:-)

Comment on Redis: Relations in a NoSQL world: Using Hashes by Brian Nesbitt

Brian Nesbitt — Thu, 25 Mar 2010 01:18:26 +0000

Just using HEXISTS creates a race condition when creating users. Using the Set will actually prevent that since the SADD is atomic and returns a success result!

There is another “smembers” call when deleting a user that should be “sismember”

Comment on Redis: Relations in a NoSQL world: Using Hashes by Adam

Adam — Thu, 25 Mar 2010 00:31:01 +0000

Hey Brian,

Thanks for the comments.

In using the ‘set’ as opposed to the HEXISTS command, that’s mostly just a carry over from the previous example.

I was using the sets mostly to maintain a consistency from the previous example to compare the difference in implementation in the storage of passwords between related keys and the newer hash functionality

As for 2 and 3… Yep, good catches, those are bugs. I’ve corrected both this post and the previous post to reflect them. Thanks for the catch.

Comment on Redis: Relations in a NoSQL world by Adam

Adam — Thu, 25 Mar 2010 00:29:18 +0000

Bug correction from Brian: http://degizmo.com/2010/03/24/redis-relations-in-a-nosql-world-using-hashes/#comments