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Today’s Top Tech Skills

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Re: Today’s Top Tech Skills

#151

Post by henrik_w »

dathinab wrote: post #25

In the recent two or so years I was surprised to see how many people don't _really_ know about SQL. Sure they can write a simple insert and update query and maybe a join, assuming they can just ignore that there actually are different types of joins. But if you ask them about other _still fundamental_ knowledge like a _rough_ idea about what the different transaction isolation level are/mean/imply for you, they fail…

I never learnt SQL "properly" until I took one of the first MOOC courses, Introduction to Databases by Jennifer Widom. Really good for getting a better understanding. Also, for a fantastic source on database transactions and isolation levels, check out "Designing Data-Intensive Applications" (chapter 7) by Martin Kleppmann. Really a great book!

I have written about both these here:

https://henrikwarne.com/2011/12/18/introduction-to-databases...

https://henrikwarne.com/2019/07/27/book-review-designing-dat...

Re: Today’s Top Tech Skills

#152

Post by pjmlp »

ellius wrote: post #137
jmartrican wrote: post #83

In Java I'm a big fan of using SQL directly versus ORM. To that end I highly recommend JOOQ. I library that allows for object oriented SQL. Its not ORM, so you still compose SQL, you just get a lot objects and methods to allow you to construct your SQL in an OO, and functional, programming type way. It also is a DB first approach. Where you construct your DB schemas and tables first, then use JOOQ to create objects t…

My team (Spring Boot / Angular greenfield app in an enterprise) has a guy that transitioned over from .NET and is totally new to the Java ecosystem. He has 30+ years experience with SQL and can't stand entity frameworks or make them do the best-practice stuff he knows we should be doing, but with JOOQ he's had a lot of success bringing his extensive knowledge base to bear on our project.

I fully understand him.

Dapper or ADO.NET, and with my Java hat on, myBatis.

Re: Today’s Top Tech Skills

#153

Post by ken »

StriverGuy wrote: post #43
dathinab wrote: post #25

In the recent two or so years I was surprised to see how many people don't _really_ know about SQL. Sure they can write a simple insert and update query and maybe a join, assuming they can just ignore that there actually are different types of joins. But if you ask them about other _still fundamental_ knowledge like a _rough_ idea about what the different transaction isolation level are/mean/imply for you, they fail…

Regarding your 2nd point: commercial grade NoSQL db's can do all of these things now. I think the notion that they cannot is from the v1-2 era of Mongo about 7 years ago. You should read the Dynamo white paper and subsequent documentation on write consistency, transactions etc. and also look at the feature set available on Mongo V4.2.

Commercial grade databases have done all these things since the 1980's. We just hadn't invented the name "NoSQL" for them, because we hadn't yet realized we were supposed to hate SQL. We called them Object Databases, because it was the decade when objects were cool. It also gave us C++ and Objective-C and Object Pascal. Basically we were just gluing objects onto everything we could.

I've used one. It was great. They (mostly) failed because of business and politics and a whole lot of other reasons unrelated to the technology. I'm sure by now everybody here knows that systems don't succeed or fail based purely on the technical qualities of their design and implementation.

Re: Today’s Top Tech Skills

#154

Post by mmsimanga »

geitir wrote: post #140
mmsimanga wrote: post #122

Earlier quoted context omitted.

Some months ago I sat in a meeting to discuss design and implementation details for a medicine delivery system. The fact that it was about medicine I thought it would be obvious to everyone that we would have to use a relation database with ACID properties. Last thing we want is to send medicine at best effort, I assumed everyone would be on the same page on the need to use transactions, foreign keys and all other da…

So they went with a non relational?

I wasn't invited back so I don't know. The back story is there had been some initial discussions before the meeting I attended. I was invited because my area is data analytics so the project owner wanted to keep me in the loop. It appears I upset the apple cart with my opinions. I was polite but firm. I don't regret it because I spend my life cleaning up messy data from systems not using core relational principles to get analytics out. Very few systems use foreign keys.

Re: Today’s Top Tech Skills

#155

Post by LaGrange »

MatekCopatek wrote: post #68
dathinab wrote: post #25

In the recent two or so years I was surprised to see how many people don't _really_ know about SQL. Sure they can write a simple insert and update query and maybe a join, assuming they can just ignore that there actually are different types of joins. But if you ask them about other _still fundamental_ knowledge like a _rough_ idea about what the different transaction isolation level are/mean/imply for you, they fail…

What would you say is the special thing about this particular bit of knowledge that made you point it out? To be perfectly honest, it seems quite arbitrary to me. I could say I'm surprised to see how many people don't know anything about the browser rendering pipeline and consequently produce badly performing interfaces. Someone else would complain about people's inability to do even the most basic Linux administrati…

> I could say I'm surprised to see how many people don't know anything about the browser rendering pipeline and consequently produce badly performing interfaces.

I mean, if you're supposed to be a senior front-end dev then that wouldn't be an unreasonable expectation. Meanwhile there's plenty of senior back-end developers out there working on SQL-backed applications who don't know SQL and refuse to learn it.

Re: Today’s Top Tech Skills

#156

Post by wehrkeoruw »

yowlingcat wrote: post #115
jackcodes wrote: post #100

Earlier quoted context omitted.

I think the point to be made was that if you screw up your browser rending to the point of it being unusable on old devices, that could be just as business critical as the data integrity issue. Making either of those your line in the sand for what a developer should and shouldn’t know is arbitrary. I don’t know a ‘Scala’ full-stack developer that could do advanced optimisation on React render times, or a ‘React’ deve…

The difference is that if you screw up your browser rendering, you're not messing up your data integrity at rest and creating compound technical and potential business debt. If anything in the critical path from pricing to payments that talks to your data store makes a mistake, you can risk anything from not recording your transactions properly to charging the wrong amount or not enough at all. It's very expensive to…

We're having this conversation as if everyone making SQL queries is one fat finger away from irrevocable data loss. I know very little about SQL but have managed to build literally dozens of systems on top of Postgres without ever causing a data loss event as a result of my poor SQL skills...

Re: Today’s Top Tech Skills

#157

Post by nostrebored »

ownagefool wrote: post #108
chrisseaton wrote: post #18

Earlier quoted context omitted.

Different clouds operate in different ways - people probably want the skill of knowing how the various parts of AWS best integrate and I’m sure that there is a lot of subtlety and non-obvious things to this. Seems reasonable to me? I don’t think it’s disturbing to seek a specific practical skill that you know you need. Not everyone has to be a master of everything.

I think the biggest problem with hiring an AWS or Azure consultant, is you might not get someone who actually does infrastructure as code (at least this happens a fair bit in London). I'd rather hire someone who knows terraform and another cloud, than somebody who'll click on the GUI for my preferred cloud, and make excuses around not being able to follow process.

This is insane -- how do these people pass through an interview?

Re: Today’s Top Tech Skills

#158

Post by Aperocky »

dagss wrote: post #138
Aperocky wrote: post #105

Earlier quoted context omitted.

TBF, sql queries is something you _don't_ want to have in your code stack. It should be abstracted away in some kind of DAO, and no one should be worrying about SQL queries when they're developing new features.

I strongly disagree. For many backends/purposes, SQL is really the thing doing all the real work and the backend's just some fancy authentication and validation layer. Stick close to the technology doing the heavy lifting. If people abstract away SQL too much they just start reimplementing things in buggy underperforming code, using 1000 lines of Go or Java or whatever what should be done in 20 lines of SQL. Also, do…

And that's a problem - my opinion remain that individual sql queries are better left for analyst and data engineers to craft so they can discover whatever correlation they might be interested in. But for a full scale app it shouldn't be in the forefront, at least not in the same package as other logic.

The entire idea of programming is the one where you abstract away things and then abstract away the thing you're currently writing. I agree that it has gone too far in some of the places, but abstracting SQL away is the first and almost one of the best abstraction you can make.

Re: Today’s Top Tech Skills

#159

Post by arcticfox »

ThrowawayR2 wrote: post #136
littlecranky67 wrote: post #101

Earlier quoted context omitted.

Again, arbitrary. You could also argue a JavaScript bug on your site preventing a shop checkout is the worst, because you lose Cash by the minutes.

You have got to be kidding. Corrupting data for a sale already made is far worse than losing a sale because of an outage.

> Corrupting data for a sale already made is far worse than losing a sale because of an outage.

I mean, this is still arbitrary. There are millions of small businesses worldwide that do fine with terrible records, but making on-going sales.

If you don't make any sales because of constant outages, you could argue that's worse than trying to deal with corrupted data, especially if you have log files or some other method to recover corrupted data anyways.

Re: Today’s Top Tech Skills

#160

Post by pjmlp »

murukesh_s wrote: post #13

Java is still undisputed in the enterprise. Node.js was a contender but lost steam. May be .net once it becomes truly platform neutral have a chance to take on Java. Until then most probably it will remain widely popular.

Depends on the enterprise.

I pretty much keep using Java and .NET alongside each other, because all the customers have mixed systems.

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