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Comment by bugbuddy | Hacker News Reader

Call a masochist but I love me good old SQL. I find most problems with systems I have worked with are the result of managements putting people who never paid attention in database classes in charge. Or maybe nobody really cares about doing a good job. In any case, my professors would have given all the legacy SQL databases that I have come across F-.

The worse part is nobody dares changing anything because it would require application code changes. Don’t blame SQL. Blame incompetent people doing SQL badly.

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I didn’t “get” SQL for the first 6-8 years of professional full-stack engineering. I was chasing, along with many in my cohort, the ORM abstraction dragon we thought we needed to work on j2ee, django, or sqlalchemy teams quickly.

It’s perplexing to me now why SQL was perplexing. Even knowing about relational theory and enough DBA to pass interviews, it somehow always seemed like we should have been able to treat databases like our OOP’s.

To think of the hours I wasted. Maybe I heard in a meeting “it’s the join table” and another colleague said “just use the association table,” and I was trying the n^2 debugging approach to solve it with model classes.

The best advice I got on this made sense later: “I wouldn’t even try to manage that [dataset] myself. Just figure out how to tell a database to do it—that’s its only job.”

Understanding relational algebra helps you write better SQL the way understanding lambda calculus helps you write better JavaScript. The language is warty and but a shadow of the pristine purity underneath, but it gets the job done and the theory guides your reasoning on how to use the language.

In particular, I find the closure property of SQL very helpful and always think in terms of queries gettings tables and producing tables (derived most of the time). https://en.wikipedia.org/wiki/Closure_(mathematics)

I really "got" SQL about 15 years after I started using it. The explanation is very simple: until that moment, SQL was a minor component for me in a big pie. Then one day I got into the position to troubleshoot some apps with >1 TB database behind them and I figured that SQL is more than simple CRUD operations. For most full stack developers that I know, SQL is still that minor component in the back of their mind and they are usually right.

Agreed, though disagree about the database class thing. I got a C in my class. I was a DBA at the time and definitely knew my shit. That was kind of the issue. He was teaching by the book with no regard to the database engine used. I was using SQL Server and MySQL daily.

There was a fundamental disconnect. I approached a class project differently not only because I was a DBA, but I am neurodivergent. Because my design didn’t align with his expectations, I got a C.

I had a 4.0 GPA prior to that, but that made me realize I wasn’t a fit for college.

Good thing as well because I am debt free today.

I failed COBOL in college in a similar situation: I was professionally writing COBOL, my project was too divergent from what the teacher expected. I took that exam 3 times to barely pass. Good times, good times.

i took compilers and prof wanted us to write lexer code by hand for a specific language. instead i wrote a generic lexer generator and fed in the language definition to generate the lexer code, got a bad grade for not following instructions. it seems kind of funny now but at the time i was rather cross.

I also got a C in my cs relational databases class. I also got more out of that class than just about any other in CS. I'm still kind of mad about it though. We had a group project assignment and our group had far-and-away the best project, of which I did 90% of the work. My bad grade came down to just one thing: the class required us to use Oracle and I refused on moral grounds.

In my experience few CS students seem to take a relational databases course. It was optional in my program. Unfortunately, that means many of those databases were created by folks with no formal grounding in databases. Some folks pick it up on their own, but likely not as thoroughly as those who've taken a good course on the topic.

> Blame incompetent people doing SQL badly.

Everything you spoke to is around people doing relational algebra badly. That has little to do with SQL. The same mistakes would lead to the same problems if the database used, say, QUEL instead.

Perhaps it's not SQL that you love at all?

Yes, people who don't understand SQL databases can easily create "F-" situations. The problem is that people who are great at SQL databases can't do any better than a C+ because that's as good as SQL gets.

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