basics

Cassandra 101 : Understanding What Cassandra Is

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As some of you may know, in my current role at Pythian I am tackling OSDB, and Cassandra is on my radar. One of the things I have been trying to do is learn what Cassandra is, so in this post, I’m going to share a bit of what I have been able to learn….

Good Database Design is Mightier than Hardware

Have you ever heard the one about throwing hardware at a software problem? I have this nifty RAC system that supports some very public and very mission-critical apps, and one day (it was Sunday night) it starts choking. We’re getting enqueues. Slowly they start climbing. Ten nodes came to a crashing halt. I have now seen a ten-node RAC cluster come to crashing halt and completely lock up. Why, you ask? A simple SQL statement: DELETE FROM a WHERE b=c AND d=e;.