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rustyrazorbladeon Ask HN: How does Cassandra achieve strong consistency if there is no rollback?

It sounds like you're conflating strong consistency with ACID transactions. The strong consistency guarantee with QUORUM writes with Cassandra is only if the write is acknowledged as successful. If you write something successfully, you'll be able to read it. When a write fails the end state is undefined.

The definition of strong consistency does not require a rollback, nor does it define the behavior of the system during a write failure. Strong consistency makes no assertions regarding atomicity (all or nothing) or isolation.

rustyrazorbladeon Getting Started with Graph Databases

Hi. Presenter here. Honestly the goal wasn't to sound fancy. If you're going to work in the GraphDB world, you're going to come across this terminology.

If your concern around my intro is the complexity described of the relational world, well, that's kind of the point. Anyone with at least a few years experience in the RDBMS world has probably come across a project that's spiraled completely out of control with a outrageous number of many to many relationships that are almost impossible to work with. The role of the DBA just to manage your queries and tables is a reflection of that difficulty.

GUN looks like a cool project. Good intro, & thanks for the feedback.

rustyrazorbladeon Getting Started with Graph Databases

You're right, there's some inconsistencies in the code vs the slides. Must have missed that. I'll fix that going forward.

rustyrazorbladeon Ways to Minimize Employee Retention

Nope, quite the opposite (at least the part about me). I'm the guy that loves & thrives on talking to people.

rustyrazorbladeon Ways to Minimize Employee Retention

On the contrary, I love what I do and the company I work for. This has nothing to do with my employer.

rustyrazorbladeon Redis as the primary data store

I built out a connection pool for the Python redis client for these types of setups where you'd want master / slave failover. It's meant to be paired with something like sentinel or custom failover scripts. https://github.com/StartTheShift/jondis

rustyrazorbladeon Titanium – a Clojure graph library built on top of Titan

We just started using Titan in production last week for shift.com, on a 3 node cassandra cluster. We open sourced our Object Graph Mapper library for Python here:

https://github.com/StartTheShift/thunderdome

There's a few caveats that come with working with distributed databases, so it's important to know what you're getting into. Neo4j might be easier out of the box (since more people are using it), but if you want a robust solution that'll work for 50 or 50,000 users, Titan feels like the way to go.