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Ask HN: What could a modern database do that PostgreSQL and MySQL can't

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Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#271

Post by ahoka »

bostik wrote: post #249
zem wrote: post #140

Earlier quoted context omitted.

don't underestimate the importance of convenience. I'm convinced one of the reasons MySQL had so much more mindshare than postgres back in the day was that it was far easier to get up and running, even if postgres might have been easier to use once everything was set up correctly.

That's funny, I must have been an outlier then. I've been using Postgres since 1998, and I tried getting MySQL up first. There was more documentation available for the latter, so it should have been simple. Failed. It just didn't work. Out of frustration I then tried Postgres, because I just wanted a decent database for my project. It was surprisingly easy, I only had to learn about pg_hba.conf to get to a functional…

No one cares what was in 1998, that's the whole point of this discussion. Postgres devs kept digging their heads into sand for many years, saying that high availability is somehow not the task of the database. In reality only the datastores need to be HA/durable in an otherwise stateless architecture.

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#272

Post by throwaway_pdp09 »

GeneralMayhem wrote: post #260
papaf wrote: post #254

Earlier quoted context omitted.

Two things stick out here that I don't fully understand. Declarative schemas, and a well-defined update process (that isn't human-written DDL), are essential at any sort of organizational scale. Isn't this impossible because some schema changes require data migration? A data migration cannot be declaratively automated as far as I know. Queue support Why not use a dedicated and feature rich queue such as Rabbit MQ or,…

>Isn't this impossible because some schema changes require data migration? In the most general case, sure - although there are workarounds for some specific cases (e.g., including previously-known-as names in the declarative schema to allow automatically planning renames). But 99% of the time, you're adding and removing tables and columns in a way that's very well defined. This is one of those areas where the best so…

I'm doing a project perhaps relevant to this. Talk of declarative schemas (or what you imply they offer) is very interesting and I'd like to know more but I can't find anything relevant (just magento and sqlalchemy). Indeed, searching for >> in google gets this very thread on the first results page.

Any links to clear, actionable and reasonably comprehensive examples of these would be most helpful. Obviously abstract statements of the required semantics are also needed, but I also need to see what actual code would look like.

TIA

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#274

Post by traceroute66 »

lazy_kangaroo wrote: post #263
yarcob wrote: post #261

Earlier quoted context omitted.

> Horizontal scaling I think the importance of horizontal scaling is overhyped. 99% of PostgreSQL applications are at a size where a single machine can easily handle the workload. To enable horizontal scaling, you need to make so many tradeoffs that I don't think it's worth it for most applications.

where did you get the 99% metric ? Most of the companies even with a single saas product have insane amount of data these days. Not just application data, There is also a whole lot of analytical data collected at every step of the product usage cycle.

> where did you get the 99% metric ? Most of the companies even with a single saas product have insane amount of data these days.

I will just leave this link here ....

https://letsencrypt.org/2021/01/21/next-gen-database-servers...

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#275

Post by bullen »

The problem with SQL databases is that the earliest where designed before the internet became widespread.

So they have synchronized clients that do not use HTTP or JSON. You need asynchronous clients that do not consume thread context switches.

Also you always want to replicate all data in more than one location in real-time because 100% read uptime is really easy to provide, while 100% write uptime is a complex nightmare.

I made this database after using MySQL, Oracle and Postgres for 10 years (it's a 2000 line replacement for my needs that these databases filled, a very narrow subset of the features you'll find in legacy databases): http://root.rupy.se

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#276

Post by traceroute66 »

tuckerconnelly wrote: post #42
traceroute66 wrote: post #23

Earlier quoted context omitted.

> It has broad PGSQL language compatibility Depends how you define broad. :) Many key features are missing, including but not limited to: - UDFs and sprocs. - Useful datatypes such as TSTZRANGE - More limited constraints I was recently looking at Cockroach as a PGSQL replacement because of its distributed nature. But the equivalence featureset is still lagging badly, unfortunatley.

Are you still using postgres? Thinking about a similar transition, would really appreciate any shared learnings :)

> Are you still using postgres?

At the moment yes.

The final decision has not been made yet, but I think the reality is we're getting tired of evaluating all these distributed databases that claim Postgres compatibility only to find its the usual clickbait marketing speak.

So the most likely outcome is we're going to stick with Postgres and give the emerging distributed tech a couple more years to pull their socks up. We're not going to go round changing all our Postgres code and schemas just to shoehorn into the limitations of a random definition of "postgres support".

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#277

Post by bbsimonbb »

takeda wrote: post #229
charlysl wrote: post #145

Earlier quoted context omitted.

> Zero impedance mismatch between database and application representation Does this include informacion hiding/encapsulation? (to prevent saved objects' internal representation from being exposed). Traditional databases don't have an encapsulation mechanism AFAIK, which is one of the reasons for impedance mismatch. This is important because it is a good practice for client code to make no assumptions about the intern…

> Traditional databases don't have an encapsulation mechanism AFAIK, which is one of the reasons for impedance mismatch. It actually does, those are views and functions. The real problem with impedance mismatch is that SQL is declarative (you say what you want and database figures out how to get it) when most programming languages are iterative (you say what should be done). The issue is that you have two very differ…

Not just jetbrains. pgtyped does this for postgres and typescript, and queryfirst for c# against sql server/postgres/mysql.

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#278

Post by GeneralMayhem »

throwaway_pdp09 wrote: post #272
GeneralMayhem wrote: post #260

Earlier quoted context omitted.

>Isn't this impossible because some schema changes require data migration? In the most general case, sure - although there are workarounds for some specific cases (e.g., including previously-known-as names in the declarative schema to allow automatically planning renames). But 99% of the time, you're adding and removing tables and columns in a way that's very well defined. This is one of those areas where the best so…

I'm doing a project perhaps relevant to this. Talk of declarative schemas (or what you imply they offer) is very interesting and I'd like to know more but I can't find anything relevant (just magento and sqlalchemy). Indeed, searching for >> in google gets this very thread on the first results page. Any links to clear, actionable and reasonably comprehensive examples of these would be most helpful. Obviously abstract…

Magento (the new XML-based version, not the old create/update/revert-script version) gives a lot of these properties. Making it part of the database instead of a third-party tool would be better, though - it lets you cover more features, and with deeper integration you can get transactional updates and history logs.

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#279

Post by mosselman »

lazy_kangaroo wrote: post #263
yarcob wrote: post #261

Earlier quoted context omitted.

> Horizontal scaling I think the importance of horizontal scaling is overhyped. 99% of PostgreSQL applications are at a size where a single machine can easily handle the workload. To enable horizontal scaling, you need to make so many tradeoffs that I don't think it's worth it for most applications.

where did you get the 99% metric ? Most of the companies even with a single saas product have insane amount of data these days. Not just application data, There is also a whole lot of analytical data collected at every step of the product usage cycle.

You are right, the metric should probably be 99.999999999999999%. 99% is way to conservative.

Re: Ask HN: What could a modern database do that PostgreSQL and MySQL can't

#280

Post by takeda »

bbsimonbb wrote: post #277
takeda wrote: post #229

Earlier quoted context omitted.

> Traditional databases don't have an encapsulation mechanism AFAIK, which is one of the reasons for impedance mismatch. It actually does, those are views and functions. The real problem with impedance mismatch is that SQL is declarative (you say what you want and database figures out how to get it) when most programming languages are iterative (you say what should be done). The issue is that you have two very differ…

Not just jetbrains. pgtyped does this for postgres and typescript, and queryfirst for c# against sql server/postgres/mysql.

I did not know that, I first encountered that in PyCharm.

I'm glad there's more.

Edit: actually what you mentioned is slightly different. This is what I'm talking about: https://youtu.be/_FlpiNno088?t=2863

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