Startups should use a relational database • Hacker News Board

Re: Startups should use a relational database

#11

Post by [deleted] » Sun, Dec 22, 2013, 8:41 AM UTC

charliesome wrote: post #5

RyanZAG wrote: post #4

Depends what your startup is doing. If you are only using your database to store some basic transactions, then a relational database is a very good fit. This is really the case for most startups tackling common problems. However, if your startup is tackling a problem with unique technical challenges, then you can't just ignore the issue. For example, a geo-location startup tracking the location in real time of users…

> For example, a geo-location startup tracking the location in real time of users with a free app is simply not going to be able to use a relational database. Why not?

[deleted]

Re: Startups should use a relational database

#12

Post by nostromo » Sun, Dec 22, 2013, 8:49 AM UTC

robconery wrote: post #9

One thing that could likely get you fired rather quickly is running analytics on your live transactional system. Yes, your business needs to make decisions based on data, this is not terribly new. To think that you only have one data store is a bit short-sighted. Many businesses (including startups) have moved to using document stores for high read environments and scraping nightly drops to their backend analytics sy…

The disconnect between your comment and the article is the term "startup" now means giant companies like Airbnb and tiny two person companies that haven't yet created an MVP.

I think this article is targeted at the latter: pre-MVP and just post-MVP. For those startups, having two databases with one dedicated to a backend analytics system reeks of premature optimization.

Re: Startups should use a relational database

#13

Post by [deleted] » Sun, Dec 22, 2013, 8:51 AM UTC

robconery wrote: post #9

One thing that could likely get you fired rather quickly is running analytics on your live transactional system. Yes, your business needs to make decisions based on data, this is not terribly new. To think that you only have one data store is a bit short-sighted. Many businesses (including startups) have moved to using document stores for high read environments and scraping nightly drops to their backend analytics sy…

[deleted]

Re: Startups should use a relational database

#14

Post by jahewson » Sun, Dec 22, 2013, 8:54 AM UTC

pkolaczk wrote: post #8

He forgot one of the very important reasons to use (some) NoSQL databases: high availability. Relational database systems are very poor at providing that. Most often the availability options are limited to resistance to node failures. RDBMSes have several SPOFs and must use failover which is not dependable, hard to test, and in many times needs manual intervention. Forget resistance to network partitions.

CAP theorem tells us that you can't have availability without sacrificing consistency or partition tolerance, which means that there isn't a NoSQL database which can do that either.

It is not true that relational databases must have a single point of failure (SPoF) or must use failover: MySQL Cluster is a sharded multi-master distributed database without a SPoF.

On the other hand Redis, for example, is a master-slave failover NoSQL datastore.

Re: Startups should use a relational database

#15

Post by robbles » Sun, Dec 22, 2013, 9:00 AM UTC

RyanZAG wrote: post #4

Depends what your startup is doing. If you are only using your database to store some basic transactions, then a relational database is a very good fit. This is really the case for most startups tackling common problems. However, if your startup is tackling a problem with unique technical challenges, then you can't just ignore the issue. For example, a geo-location startup tracking the location in real time of users…

I don't see why not - use a relational database for storing long-term data, such as users, friendships, preferences, etc. and store ephemeral data such as location in a key-value store like Redis. Store summary statistics of the location data in your primary data store in scheduled background tasks.

Just because you're storing a huge amount of one specific type of data, that doesn't prevent you from taking advantage of the features of a relational database.

Re: Startups should use a relational database

#16

Post by Sanddancer » Sun, Dec 22, 2013, 9:04 AM UTC

RyanZAG wrote: post #4

Depends what your startup is doing. If you are only using your database to store some basic transactions, then a relational database is a very good fit. This is really the case for most startups tackling common problems. However, if your startup is tackling a problem with unique technical challenges, then you can't just ignore the issue. For example, a geo-location startup tracking the location in real time of users…

Precluding yourself from using a relational database means that you're not going to be able to use some of the best tools available for geographical data. Things like PostGIS are built around, and heavily dependent on, the fact that it is Postgres. Now, you may not want to use an RDBMS for everything, but at the same time, you don't want to pull it completely out of the system either.

Re: Startups should use a relational database

#17

Post by [deleted] » Sun, Dec 22, 2013, 9:13 AM UTC

robconery wrote: post #9

One thing that could likely get you fired rather quickly is running analytics on your live transactional system. Yes, your business needs to make decisions based on data, this is not terribly new. To think that you only have one data store is a bit short-sighted. Many businesses (including startups) have moved to using document stores for high read environments and scraping nightly drops to their backend analytics sy…

[deleted]

Re: Startups should use a relational database

#18

Post by gaius » Sun, Dec 22, 2013, 9:21 AM UTC

pkolaczk wrote: post #8

He forgot one of the very important reasons to use (some) NoSQL databases: high availability. Relational database systems are very poor at providing that. Most often the availability options are limited to resistance to node failures. RDBMSes have several SPOFs and must use failover which is not dependable, hard to test, and in many times needs manual intervention. Forget resistance to network partitions.

None of what you wrote is true.

Re: Startups should use a relational database

#19

Post by HorizonXP » Sun, Dec 22, 2013, 9:21 AM UTC

Serious question: what are NoSQL databases really good for? I'm only really used to relational DBs, and I'm unclear about which problems a NoSQL database is useful for.

Re: Startups should use a relational database

#20

Post by BadassFractal » Sun, Dec 22, 2013, 9:25 AM UTC

HorizonXP wrote: post #19

Serious question: what are NoSQL databases really good for? I'm only really used to relational DBs, and I'm unclear about which problems a NoSQL database is useful for.

Take Redis for example: simple KV database with in-memory perf and a very comfortable API with option to flush data to disk periodically. Addresses a lot of interesting scenarios such as session storage, request throttling by a certain key etc. Not used as a replacement for a RDBMS most of the time, but rather as a specialized tool for a certain use case. At some point your RDBMS is already hammered hard enough, you don't need to dump everything into it, but ultimately you could, especially at first. Comes with clustering for free as long as you're aware of the risks and use it appropriately.

This is not to say you couldn't turn Postgres into something similar. Put the data on a ramfs, relax various write guarantees (lots of knobs in PG) etc.