5 ms·

I’d be a lot more sympathetic if the major RDMSes didn’t have outstanding and thorough reference manuals or that there weren’t a mountain of books on the subjec

I’d be a lot more sympathetic if the major RDMSes didn’t have outstanding and thorough reference manuals or that there weren’t a mountain of books on the subject that cover, among other things, the topic of indexing and its importance. MySQL’s manual, for example, has covered this subject from the very beginning: https://dev.mysql.com/doc/refman/5.6/en/mysql-indexes.html https://dev.mysql.com/doc/refman/5.6/en/mysql-indexes.html (I don’t have the 3.x manuals handy but it was there back then too). It’s not clear from the article whether the author spent any time studying the problem before implementing it. If she failed to do so, it is both problematic and way more common than it ought to be. “Ready, fire, aim” But you know what they say: good judgment comes from experiences and experience comes from bad judgment. Compounding the problem here is that the author now has much more experience and in a reflective blog post, still got the wrong answer. IMO the better lesson to take away here would have been to take the time getting to know the technology before putting it into production instead of jumping head first into it. That would be bar raising advice. The current advice doesn’t advise caution; instead it perpetuates the status quo and gives “feel good” advice.

dasil003 5y ago
I couldn't disagree more with this comment. No amount of reading documentation teaches you how to build production systems. You progress much faster by getting your hands dirty, making mistakes, and learning from them. The challenge of writing good software is not about knowing and focusing on the perfection every gory detail, it's about developing the judgement to focus on the details that actually matter. Junior engineers who follow your advice will be scared to make mistakes and their development will languish compared to those who dive in and learn from their mistakes. As one gains experience it's easy to become arrogant and dismissive of mistakes that junior engineers make, but this can be extremely poisonous to their development.
- noduerme 5y ago
  But it's also about constantly asking yourself "how can this be done better? What do I not know that could improve it?" I learned probably 80% of what I know about DB optimization from reading the Percona blog and S.O. The other 20% came from splashing around and making mistakes, and testing tons of different things with EXPLAIN. That's basically learning in a vacuum.
- deleted 5y ago
  [deleted]
- isoskeles 5y ago
  I couldn't disagree more with this comment. No amount of getting your hands dirty and making mistakes teaches you how to learn from your mistakes, nor changes the impact of the mistakes. You also progress much faster by learning from other peoples' mistakes, this is why written language is so powerful. Honestly, I think your comment is okay minus the fact that you're trying to highlight such hard disagreement with a sentiment that people should read the fucking manual. Really, you couldn't disagree MORE? There is definitely value in RTFM. There are cases where making mistakes in production is not acceptable, and progressing by "making mistakes" is a mistake on its own. I don't think the case in this article sounds like one of those, but they do exist (e.g. financial systems (think about people losing money on crypto exchanges), healthcare, or, say, sending rockets into space). In many cases, making mistakes is fine in test systems, but completely, absolutely, catastrophically unacceptable in production. Although, I refuse to blame the junior engineer for such mistakes, I blame management that "sent a boy to do a man's job" (apologies for a dated idiom here). (As an aside, overall, I disagree with many of the comments here nitpicking the way the author solved the problem, calling her "clueless", etc. I really don't care about that level of detail, and while I agree the solution does not seem ideal, it worked for them better than the previous solution.)
  - crispyambulance 5y ago
    > No amount of getting your hands dirty and making mistakes teaches you how to learn from your mistakes... Categorically wrong. Mistakes, failure, and trial and error are very much a part of developing skills. If you're not making mistakes, you're also not taking enough risks and thus missing out on opportunities for growth.
    - isoskeles 5y ago
      Yes, mistakes are required to learn from them, but making mistakes does not imply that a person will learn from their mistakes.
- otterley 5y ago
  Respectfully, I believe you are disagreeing with an argument that I am not making. It's not an either-or scenario. Both access to and reliance on reference materials and the ability to safely experiment are part of the professional engineer's toolbox. I can say this with confidence because I was a junior engineer once - it's not like I'm speaking without experience. Everyone - new and experienced developers alike - should have a healthy fear of causing pain to customers. Serving customers - indirectly or otherwise - is what makes businesses run. As a principal engineer today my number one focus is on the customer experience, and I try to instill this same focus in every mentee I have. Does that mean that junior developers should live in constant fear and decision paralysis? Of course not. That's where the mentor - the more experienced and seasoned engineer - comes in. The mentor is roughly analogous to the teacher. And the teaching process uses a combination of a mentor, reference materials, and the lab process. The reference materials provide the details; the lab process provides a safe environment in which to learn; and the mentor provides the boundaries to prevent the experiments from causing damage, feedback to the mentee, and wisdom to fill in the gaps between them all. If any of these are absent, the new learner's development will suffer. Outstanding educational systems were built over the last 3 centuries in the Western tradition using this technique, and other societies not steeped in this tradition have sent their children to us (especially in the last half-century) to do better than they ever could at home. It is a testament to the quality of the approach. So no, I'm not advocating that junior developers should do nothing until they have read all the books front to back. They'd never gain any experience at all or make essential mistakes they could learn from if they did that. But junior developers should not work in a vacuum - more senior developers who both provide guidance and refer them to reference materials to study and try again, in my experience, lead to stronger, more capable engineers in the long term. "Learning to learn" and "respect what came before" are skills as important as the engineering process itself.
  - crispyambulance 5y ago
    > That's where the mentor [...] comes in. The thing is, specifically, that the OP did NOT have a mentor. They had a serious problem to solve, pronto, and knew enough to take a crack at it. OK, the initial implementation was suboptimal. So what? It's totally normal, learn and try again. Repeat. It would be nice if every workplace had a orderly hierarchy of talent where everyone takes care to nurture and support everyone else (especially new folks). And where it's OK to ask questions and receive guidance even across organizational silos, where there are guardrails to mitigate accidents and terrible mistakes. If you work in such an environment, you are lucky. It is far more common to have sharp-elbow/blamestorm workplaces which pretend to value "accountability" but then don't lift a finger to support anyone who takes initiative. I suspect that at the time Rachelbythebay worked in exactly this kind of environment, where it simply wasn't possible for an OPS person to go see the resident database expert and ask for advice.
jraph 5y ago
You can't really search a problem if you don't suspect its existence. At this point you might feel you have everything you need to start the implementation, how do you guess?

dasil003 5y ago

I couldn't disagree more with this comment. No amount of reading documentation teaches you how to build production systems. You progress much faster by getting your hands dirty, making mistakes, and learning from them. The challenge of writing good software is not about knowing and focusing on the perfection every gory detail, it's about developing the judgement to focus on the details that actually matter. Junior engineers who follow your advice will be scared to make mistakes and their development will languish compared to those who dive in and learn from their mistakes. As one gains experience it's easy to become arrogant and dismissive of mistakes that junior engineers make, but this can be extremely poisonous to their development.

noduerme 5y ago
But it's also about constantly asking yourself "how can this be done better? What do I not know that could improve it?" I learned probably 80% of what I know about DB optimization from reading the Percona blog and S.O. The other 20% came from splashing around and making mistakes, and testing tons of different things with EXPLAIN. That's basically learning in a vacuum.
deleted 5y ago
[deleted]
isoskeles 5y ago
I couldn't disagree more with this comment. No amount of getting your hands dirty and making mistakes teaches you how to learn from your mistakes, nor changes the impact of the mistakes. You also progress much faster by learning from other peoples' mistakes, this is why written language is so powerful. Honestly, I think your comment is okay minus the fact that you're trying to highlight such hard disagreement with a sentiment that people should read the fucking manual. Really, you couldn't disagree MORE? There is definitely value in RTFM. There are cases where making mistakes in production is not acceptable, and progressing by "making mistakes" is a mistake on its own. I don't think the case in this article sounds like one of those, but they do exist (e.g. financial systems (think about people losing money on crypto exchanges), healthcare, or, say, sending rockets into space). In many cases, making mistakes is fine in test systems, but completely, absolutely, catastrophically unacceptable in production. Although, I refuse to blame the junior engineer for such mistakes, I blame management that "sent a boy to do a man's job" (apologies for a dated idiom here). (As an aside, overall, I disagree with many of the comments here nitpicking the way the author solved the problem, calling her "clueless", etc. I really don't care about that level of detail, and while I agree the solution does not seem ideal, it worked for them better than the previous solution.)
- crispyambulance 5y ago
  > No amount of getting your hands dirty and making mistakes teaches you how to learn from your mistakes... Categorically wrong. Mistakes, failure, and trial and error are very much a part of developing skills. If you're not making mistakes, you're also not taking enough risks and thus missing out on opportunities for growth.
  - isoskeles 5y ago
    Yes, mistakes are required to learn from them, but making mistakes does not imply that a person will learn from their mistakes.
otterley 5y ago
Respectfully, I believe you are disagreeing with an argument that I am not making. It's not an either-or scenario. Both access to and reliance on reference materials and the ability to safely experiment are part of the professional engineer's toolbox. I can say this with confidence because I was a junior engineer once - it's not like I'm speaking without experience. Everyone - new and experienced developers alike - should have a healthy fear of causing pain to customers. Serving customers - indirectly or otherwise - is what makes businesses run. As a principal engineer today my number one focus is on the customer experience, and I try to instill this same focus in every mentee I have. Does that mean that junior developers should live in constant fear and decision paralysis? Of course not. That's where the mentor - the more experienced and seasoned engineer - comes in. The mentor is roughly analogous to the teacher. And the teaching process uses a combination of a mentor, reference materials, and the lab process. The reference materials provide the details; the lab process provides a safe environment in which to learn; and the mentor provides the boundaries to prevent the experiments from causing damage, feedback to the mentee, and wisdom to fill in the gaps between them all. If any of these are absent, the new learner's development will suffer. Outstanding educational systems were built over the last 3 centuries in the Western tradition using this technique, and other societies not steeped in this tradition have sent their children to us (especially in the last half-century) to do better than they ever could at home. It is a testament to the quality of the approach. So no, I'm not advocating that junior developers should do nothing until they have read all the books front to back. They'd never gain any experience at all or make essential mistakes they could learn from if they did that. But junior developers should not work in a vacuum - more senior developers who both provide guidance and refer them to reference materials to study and try again, in my experience, lead to stronger, more capable engineers in the long term. "Learning to learn" and "respect what came before" are skills as important as the engineering process itself.
- crispyambulance 5y ago
  > That's where the mentor [...] comes in. The thing is, specifically, that the OP did NOT have a mentor. They had a serious problem to solve, pronto, and knew enough to take a crack at it. OK, the initial implementation was suboptimal. So what? It's totally normal, learn and try again. Repeat. It would be nice if every workplace had a orderly hierarchy of talent where everyone takes care to nurture and support everyone else (especially new folks). And where it's OK to ask questions and receive guidance even across organizational silos, where there are guardrails to mitigate accidents and terrible mistakes. If you work in such an environment, you are lucky. It is far more common to have sharp-elbow/blamestorm workplaces which pretend to value "accountability" but then don't lift a finger to support anyone who takes initiative. I suspect that at the time Rachelbythebay worked in exactly this kind of environment, where it simply wasn't possible for an OPS person to go see the resident database expert and ask for advice.

jraph 5y ago

You can't really search a problem if you don't suspect its existence. At this point you might feel you have everything you need to start the implementation, how do you guess?