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On Uber’s Choice of Databases
- segmondy 10y agoThis is a very good and fair response and anyone serious about tuning their DB should have use-the-index-luke.com bookmarked!
- JoachimSchipper 10y agoThis is a response to Uber's article, discussed at https://news.ycombinator.com/item?id=12166585 https://news.ycombinator.com/item?id=12166585.
- Beanis 10y agoAll of these response posts seem to miss one big piece that made no sense to me. Uber goes really in-depth around the higher cost of updates in postgres, but then Uber describes Schemaless as an immutable append only data store. They created a custom database with no updates, but one of their primary reasons for changing from postgres to mysql was because of the high cost of updates?
- superuser2 10y agoSchemaless is primarily a sharding scheme for MySQL. It's possible that using Postgres in an append-only manner would have created too many records to handle without an analogous sharding scheme.
- Beanis 10y agoFrom the little I can see from their blog posts, Schemaless seems to be both a sharding layer and an immutability layer that can sit on top of postgres or mysql. However, discussing the costs of mutable data when you have created an immutable data storage layer doesn't make much sense.
- azylman 10y agoFrom what I can tell Schemaless has updates but represents them as inserts. When you want to change something (e.g. change the billing status of a trip), it writes a new billing status for the trip and consumers will always ask for the latest billing status for the trip, which is the most recent and up-to-date one. Take this with a grain of salt, I just read the Schemaless articles yesterday.
- Beanis 10y agoThat is how I understood it too. Updating your data with a call to insert won't run into the same problems as updating your data with a call to update. Their immutability implementation seems like it would behave nearly the same under both databases.
- dorfsmay 10y agoIsn't reddit doing schema-less on postgres?
- pbreit 10y agoMost of the conversation on the topic misses that Uber's actions are totally irrelevant to 99.9% of us. Uber has unlimited resources and unique problems. Sure, it's interesting but ultimately almost entirely meaningless.
- HNSucksAss 10y agoWow, someone who knows how to spell "key/value" (it's not "key-value").
- azylman 10y agoThe money quote to me that was really interesting was this one: > for a rapidly growing company, technology is easier to change than people.
- frankwiles 10y agoThis really all boils down to "Ford F-150s are bad trucks because your cargo can get wet when it rains, use a U-Haul truck". Sure, for that VERY specific (and not very common) use case U-Hauls beat F-150s. However, I think we can all agree that F-150s are far more versitle for most use cases, up to including something trivial like heading to Starbucks for a quick coffee.