81–90 of 96 posts
Under protocols you may want to specify MongoDB's as BSON and Cassandra's as Thrift. That would be more helpful than "binary/custom". Updated: Also Redis's main selling point is it's extensive data structure/operations support. "Blazingly fast" really depends on what your workload is and what you're comparing it against.
Protocols: great idea, thanks man, amended it! Blazing fast: I mean compared to the other four.
I like this article: while it is for sure not the definitive guide to NoSQL, it is a short description mostly about facts that people new to the field can use to get an idea about what a good candidate could be for initial experimentation, given a defined problem to solve. That said I think that picking the good database is something you can do only with a lot of work. Picking good technologies for your project is ha…
This is probably the most important and relevant point I've seen in a while. Architects should take note...
Earlier quoted context omitted.
"Cassandra requires all nodes to be restarted to apply a schema change, which can be quite a big deal." That's no longer true. In 0.7, keyspaces and column families may be created, altered, or dropped live.
I thought it might have been fixed by now. Anyway, you still need a schema with Cassandra.
So if Cassandra writes are much faster than reads, why would Reddit go that route? Their comment server is consistently breaking on them, and it would seem that a sub-optimal choice of db might be partly to blame.
What is your suggestion otherwise? Any distributed database that is going to be inexpensive, performant, scalable, and durable will need to use some kind of quorum read repair system. Riak, Voldemort, and Dynamo all use read repair with high levels of production success.
You mention that some of these solution could be used in the Financial industry. I would be cautious of using these, especially since some are eventually consistent. If you are just tracking data these may be fine though.
Worth adding HBase? Much below Stolen from their overview page (All needs to be confirmed): http://hbase.apache.org/ WRITTEN IN: Java MAIN POINT: Hadoop Database LICENSE: Apache PROTOCOL: A REST-ful Web service gateway This project's goal is the hosting of very large tables -- billions of rows X millions of columns -- atop clusters of commodity hardware. HBase is an open-source, distributed, versioned, column-oriente…
There's also a region master re-election/recovery period that depends on the size of the database, network bandwidth, load, etc. It can be anywhere from 30 seconds to tens of minutes. An outage of a region node makes it's key range inaccessible. While that might not be a problem for some, especially in read-only situations, I can think of many applications where that would effectively translate into a total outage.
Earlier quoted context omitted.
With AppEngine at Google, MongoDB at Disqus, Cassandra at Facebook and Redis at Github you can definitely say that SQL databases are one of many options available today and don't dominate like they did 5 years ago.
if i'm not mistaken, the majority of those organizations still rely heavily on relational datastores, except in the case of exceptional workloads. in addition, i believe facebook has since migrated away from cassandra to the hadoop stack for their messaging platform, though they primarily use mysql (or its successors). SQL is being replaced in niches that strain its model. elsewhere, it remains steadfast.
Interesting and useful. One major feature differentiator is something it doesn't really talk about, though - how conducive is each system to Massive Data? For example, he kind of has a bone to pick with Cassandra, which is probably justified. But from what little I know, one of the features of Cassandra is that it's designed to scale pretty much to infinity. That may be true of a couple of the others, but for some (l…
Good point, and it's not there since I only wanted to speak from experience; especially with rumors of Cassandra scaling problems at Reddit and Digg. But sure thing, "infinite" scaling is probably best done with the Dynamo-like stuff like Cassandra and/or RIAK.
http://www.reddit.com/r/announcements/comments/c2spc/reddits...