https://github.com/clickhouse-elixir/clickhouse_ecto
I did not try it though as I wrote above in my first message.
focused
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Jcambass
Hi @dojap
I would suggest to stick with Postgres or MySQL unless you know why you need to choose something else.
If you’re trying to build a SaaS you will very likely run into a 1000 other problems before MySQL or Postgres will get in your way.
Personally I would recommend Postgres since IMHO it has more features to offer and good support in Ecto. If you’re already familiar with MySQL then it’s also fine to use that instead.
Instead of focusing on scaling I would focus on features offered, available documentation resources and compatibility. For ecto and Saas style apps Postgres is the first choice for me there.
Both Postgres and MySQL can scale quite well given enough hardware resources. As others have wrote, you will not hit limitations there soon. It’s very likely that app or database design decision you choose will become a problem before the actuall database engine itself.
So my personal recomendation is to go with Postgres (or MySQL if you feel more comfortable with that) and focus on start building your Saas.
For reference:
I have used Postgres in various elixir side projects where it never got into my way and was easy to “set up and forget”.
But I also use it extensively at work where we use it not only for online transactional databases but also stuff like timeseries like databases, analytical use cases and datawarehouses.
While it’s possible the tune certain Postgres settings to reach peak performance it’s not something you need to worry or even know about until you hit those limits.
Feel free to reach out and ask more specific questions. I’m pretty sure you don’t need to focus on scaling but if you know what kind of database workload you’re planning for then a more specific answer might be possible.
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dojap
Thanks for your reply. Now, I am back to zero 
. It’s hard to decide. Perhaps I will go with Postgres in the end.
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dojap
focused
dojap
hauleth
Remember that Clickhouse will be enormously slow at fetching single rows. So if your application will mostly do stuff like:
SELECT name FROM users WHERE id = 10
Then Clickhouse will make your application terribly slow (nature of column storage).
You still operate in the vague “more reads than writes” - most applications do more reads than writes. Describe directly what you want to do and how many millions of the requests you will need to handle daily. Otherwise I wouldn’t care and I would pick PostgreSQL.
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dojap
Yeah, perhaps you are right. Clickhouse seems to be good only for analytics.
One question, can you recommend some compact tutorial about Postgres? Not focused on queries but more on settings on Linux (Ubuntu) and pool size etc.?
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hauleth
Their documentation?
And for super simple generator of config that will be “ok enough” you can use PgTune and you can read PG Wiki on tuning.
Also check out this article - Elixir and Postgres: A Rarely Mentioned Problem | Lainblog
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