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Goodbye MongoDB, Hello PostgreSQL

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Re: Goodbye MongoDB, Hello PostgreSQL

#41

Post by snuxoll »

Pxtl wrote: post #27
jgrahamc wrote: post #13

As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well. The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid. And one more thing: star = Sequel.lit('*') User.select(:locale) .select_append { count(star).as(:amount) } .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percen…

I use Entity Framework as an ORM and I have to say I like it. As much as there have been a lot of false-starts related to trying to reinvent SQL, I think Entity Framework hits many of the right notes for me: 1) All my code lives in Visual Studio with compile-time type-checking. No maintaining stored procedures outside of my main codebase, no mucking about with strings. And because Entity Framework puts the Select aft…

Entity Framework still generates pretty crappy looking SQL. It's nice to get a project going, but every time I try to look at why we are having performance issues in production and see the horrible query EF is generating I cry.

Re: Goodbye MongoDB, Hello PostgreSQL

#42

Post by api »

jgrahamc wrote: post #13

As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well. The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid. And one more thing: star = Sequel.lit('*') User.select(:locale) .select_append { count(star).as(:amount) } .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percen…

Agreed, but it's important to understand what drove the adoption of NoSQL and schema-less stuff as well as the related trend of dynamic languages like Ruby and JavaScript.

(1) SQL server software itself was clunky, hard to scale, complex to deploy in a clustered fashion, and generally "old" in a bad way. This made NoSQL seem like a breath of fresh air.

(2) Startups! Ship now! MVP! Fail fast! The whole industry has been operating on this ship-fast-fail-fast way of doing things that prioritizes development speed and agility over correctness. That's because half the time what you are developing will be thrown away anyway -- it will fail, or you'll "pivot" and rip it all apart and almost start over. No point in static languages, SQL schemas, or other explicit design elements in that world.

#2 is I think the more significant of the two for things like schema-less MongoDB or dynamic languages. Once you get product/market fit, you typically end up taking the crap you wrote with no types and schemas and re-doing it in a "real language" with a "real database." But as they say in Startupistan, that's a "good problem to have."

Re: Goodbye MongoDB, Hello PostgreSQL

#43

Post by matwood »

jgrahamc wrote: post #13

As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well. The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid. And one more thing: star = Sequel.lit('*') User.select(:locale) .select_append { count(star).as(:amount) } .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percen…

I started with SQL in the 90s and completely agree with you. People who do not know SQL tend to reinvent it poorly in a language not designed to work with sets of data.

We have started using jOOQ and it strikes a great balance of raw sql/typed sql and result -> object mapping. I don't ever seen going back to a heavyweight ORM again. There is just too much magic and lost time spend figuring out performance issues for a minimal gain in ramp up for those who do not know SQL.

Re: Goodbye MongoDB, Hello PostgreSQL

#44

Post by limelight »

This post reflects an interesting technical narrative of companies switching off MongoDB to more traditional relational databases as they grow.

Importantly, I don't think that's an indictment of MongoDB. Instead, it highlights the key advantages of NoSQL: ease of use and rapid iteration.

When you're first working on a project, MongoDB is very easy to slap in. You don't even have to create tables/collections. As you iterate, you don't have to constantly be updating schemas as your product direction shifts. Thus, MongoDB is perfect for early startups.

As a company scales, of course it's warts start to show. The very attributes (like schemaless storage) which were an asset when just a few developers were hacking on the project become a drawback as the company grows in size. Reliability becomes more of a concern.

Naturally, people shift to a more traditional database. Personally, I'm almost ready to switch some of our core functionality from MongoDB to Postgres. This isn't an indictment of Mongo though.

Re: Goodbye MongoDB, Hello PostgreSQL

#45

Post by MaggieL »

limelight wrote: post #44

This post reflects an interesting technical narrative of companies switching off MongoDB to more traditional relational databases as they grow. Importantly, I don't think that's an indictment of MongoDB. Instead, it highlights the key advantages of NoSQL: ease of use and rapid iteration. When you're first working on a project, MongoDB is very easy to slap in. You don't even have to create tables/collections. As you i…

OP will be back in three years talking about migrating off of Ruby...if they make it that far :-)

Re: Goodbye MongoDB, Hello PostgreSQL

#46

Post by MaggieL »

limelight wrote: post #44

This post reflects an interesting technical narrative of companies switching off MongoDB to more traditional relational databases as they grow. Importantly, I don't think that's an indictment of MongoDB. Instead, it highlights the key advantages of NoSQL: ease of use and rapid iteration. When you're first working on a project, MongoDB is very easy to slap in. You don't even have to create tables/collections. As you i…

OP will be back in three years talking about migrating off of Ruby...if they make it that far :-)

Re: Goodbye MongoDB, Hello PostgreSQL

#47

Post by Sivart13 »

jgrahamc wrote: post #13

As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well. The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid. And one more thing: star = Sequel.lit('*') User.select(:locale) .select_append { count(star).as(:amount) } .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percen…

I assure you that whoever wrote that code knows SQL.

The builder syntax is convenient because it allows queries to be composable without ugly string-smashing. For instance, you could take the object built out of that "User.select..." and pass it around into other functions that append extra 'where' clauses, etc.

Re: Goodbye MongoDB, Hello PostgreSQL

#48

Post by aethertap »

ttty wrote: post #32
jgrahamc wrote: post #13

As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well. The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid. And one more thing: star = Sequel.lit('*') User.select(:locale) .select_append { count(star).as(:amount) } .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percen…

I sincerely still prefer mongodb syntax because: - Fits well with a programming language; {a: data.x} is better than 'WHERE A="' + data.x + '"' (sanitize?) or similar which are harder to read. SQL queries are good for direct input, mongodb queries styles are better to be used with a programming language;

Your comment made me realize why I prefer to work in ORMs instead of raw SQL, even though I'm frequently frustrated by their limitations - it all comes down to composability.

The mongodb syntax looks like it supports composing statements much more readily than SQL. It makes me wonder if there's been any serious work done making a query language that's fully as general as SQL, but is designed to be safely and easily composable so that you can build queries up from parts.

Anyone know of such a thing? The mongodb approach of query-as-data-structure is as close as I've seen.

Re: Goodbye MongoDB, Hello PostgreSQL

#49

Post by imfletcher »

while i've not spent much time with the "nosql" products, its mostly because i've decided to stay SQL. The bottom line is that most humans think of data the same way SQL thinks about data. When you talk to people outside of engineering (i.e. mgmt or customers), they expect the product to be able to do things that SQL does naturally (normalized data for easy changes to things like 'user name', join and sort based on a variety of cross cutting properties, etc). You can always make both do the same thing eventually, but one will fight you more than the other....

Re: Goodbye MongoDB, Hello PostgreSQL

#50

Post by buckbova »

The concept of moving from one database technology to another, especially something like NoSQL to Postgres, sounds like a huge task.

Aside from redesigning the schema/model and changing all the code, what about new backup/restore procedures? Scaling and performance best practices? Did you need to hire a postgres expert?

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