7 ms·
A little surprising that this article does not mention HBase which uses timestamps as part of the persisted key, while using an entirely different concept of a
by dmk23 13y ago
A little surprising that this article does not mention HBase which uses timestamps as part of the persisted key, while using an entirely different concept of a "WriteNumber" as an internal ID to resolve conflicting updates (MVCC).
This presentation might provide a helpful overview: http://www.slideshare.net/cloudera/3-learning-h-base-internals-lars-hofhansl-salesforce-final http://www.slideshare.net/cloudera/3-learning-h-base-interna...
The relevant discussion starts at Slide 16
- aphyr 13y agoWriteNumbers are a logical clock provided by (last I checked) a single coordinating HBase node, which is a totally valid and commonly used way to order operations. For the purposes of this article, though, I'm trying to focus on LWW data models and wall clocks. A discussion of every database's approach to ordering would take a little longer. ;-)