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Comment by camus2 | Hacker News Reader

did not know all that stuff, could Elasticsearch be the holy grail of document stores ?

No. The choice of datastore is still incredibly complicated in the distributed world; it's all about tradeoffs really.

For example, Elasticsearch has poor availability characteristics - both because it is master-slave and because it focuses on ensuring consistency - relative to, for example, something like Riak.

I don't believe it's "master-slave" in the way you're thinking. Elasticsearch shards its indexes among all available nodes, storing replicas of each shard on separate nodes when possible. This ensures that the entire cluster is available as long as at least one replica of a shard is still online. In fact, if configured properly, it has better availability than consistency since by default it only flushes its oplog to the Lucene index segments every second (though writes aren't considered committed until they reach a quorum of nodes, so consistency is fairly good in practice as well).

It is definitely a nice, and flexible option.. it truly depends on what your needs are... If you're often updating parts of a document, MongoDB or RethinkDB may be better options. If you want integration where a lot of parts are SQL with some document ability, PostgreSQL + V8 is pretty compelling. Also, something like Cassandra may suit your needs better if you want a better and more predictable growth curve.

There's no holy grail of data storage... ElasticSearch is really nice, and if it fits your needs, more power to you.

We'll maybe some day but it is still too easy to corrupt the data or index. Recently I had a problem where the data itself was fine and searches worked correctly but it was 100x slower than it should be. It just started happening for no apparent reason and I just do basic searches on typical data. I still don't know what happened but creating a new index fixed the problem.

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