Joël conducted a thoughtbot mini-workshop on query plans, which Stephanie found highly effective due to its interactive format. They then discuss the broader value of interactive workshops over traditional talks for deeper learning.
Addressing listener questions, Stephanie and Joël explore the strategic use of if and else in programming for clearer code, the importance of thorough documentation in identifying bugs, and the use of Postgres' EXPLAIN ANALYZE, highlighting the need for environment-specific considerations in query optimization.
- Episode mentioning query plans
- Query plan visualizer
- RailsConf 2024
- Episode 349: Unpopular Opinions
- Squint test
- Episode 405: Retro on Sandi Metz rules
- Structuring conditionals in a wizard
- Episode 417: Module docs
- Episode 416: Multidimensional numbers
- ruby-units gem
- Solargraph
- parity
Transcript:
STEPHANIE: Hello and welcome to another episode of The Bike Shed, a weekly podcast from your friends at thoughtbot about developing great software. I'm Stephanie Minn.
JOËL: And I'm Joël Quenneville, and together, we're here to share a bit of what we've learned along the way.
STEPHANIE: So, Joël, what's new in your world?
JOËL: Just recently, I ran a sort of mini workshop for some colleagues here at thoughtbot to dig into the idea of query plans and, how to read them, how to use them. And, initially, this was going to be more of a kind of presentation style. And a colleague and I who were sharing this decided to go for a more interactive format where, you know, this is a, like, 45-minute slot.
And so, we set it up so that we did a sort of intro to query plans in about 10 minutes then 15 minutes of breakout rooms, where people got a chance to have a query plan. And they had some sort of comprehension questions to answer about it. And then, 15 minutes together to have each group share a little bit about what they had discovered in their query plan back with the rest of the group, so trying to balance some understanding, some application, some group discussion, trying to keep it engaging. It was a pretty fun approach to sharing information like that.
STEPHANIE: Yeah. I wholeheartedly agree. I got to attend that workshop, and it was really great. Now that I'm hearing you kind of talk about the three different components and what you wanted people attending to get out of it, I am impressed because [laughs] there is, like, a lot more thought, I think, that went into just participant engagement that reflecting on it now I'm like, oh yeah, like, I think that was really effective as opposed to just a presentation. Because you had, you know, sent us out into breakout rooms, and each group had a different query that they were analyzing. You had kind of set up links that had the query set up in the query analyzer. I forget what the tool was called that you used.
JOËL: I forget the name of it, but we will link it in the show notes.
STEPHANIE: Yeah. It was helpful for me, though, because, you know, I think if I were just to have learned about it in a presentation or even just looked at, you know, screenshots of it on a slide, that's different still from interacting with it and feeling more confident to use it next time I find myself in a situation where it might be helpful.
JOËL: It's really interesting because that was sort of the goal of it was to make it a bit more interactive and then, hopefully, helping people to retain more information than just a straight up, like, presentation would be. I don't know how you feel, I find that often when I go to a place like, let's say, RailsConf, I tend to stay away from more of the workshop-y style events and focus more on the talks. Is that something that you do as well?
STEPHANIE: Yeah. I have to confess that I've never attended a workshop [laughs] at a conference. I think it's partly my learning style and also partly just honestly, like, my energy level when I'm at the conference. I kind of just want to sit back. It's on my to-do list. Like, I definitely want to attend one just to see what it's like. And maybe that might even inspire me to want to create my own workshop. But it's like, once I'm in it, and, you know, like, everyone else is also participating, I'm very easily peer pressured [laughs]. So, in a group setting, I will find myself enjoying it a lot more. And I felt that kind of same way with the workshop you ran for our team.
Though, I will say a funny thing that happened was that when I went out into my breakout group with another co-worker, and we were trying to grok this query that you gave us, we found out that we got the hardest one, the most complicated one [laughs] because there were so many things going on. There was, like, multiple, like, you know, unions, some that were, like, nested, and then just, like, a lot of duplication as well, like, some conditions that were redundant because of a different condition happening inside of, like, an inner statement. And yeah, we were definitely scratching our heads for a bit and were very grateful that we got to come back together as a group and be like, "Can someone please help? [laughs] Let's figure out what's going on here."
JOËL: Sort of close that loop and like, "Hey, here's what we saw. What does everybody else see?"
STEPHANIE: Yeah, and I appreciated that you took queries from actual client projects that you were working on.
JOËL: Yeah, that was the really fun part of it was that these were not sort of made-up queries to illustrate a point. These were actual queries that I had spent some time trying to optimize and where I had had to spend a lot of time digging into the query plans to understand what was going on. And it sounds like, for you, workshops are something that is...they're generally more engaging, and you get more value out of them. But there's higher activation energy to get started. Does that sound right?
STEPHANIE: Yeah, that sounds right. I think, like, I've watched so many talks now, both in person and on YouTube, that a lot of them are easily forgettable [laughs], whereas I think a workshop would be a lot more memorable because of that interactivity and, you know, you get out of it what you put in a little bit.
JOËL: Yeah, that's true. Have you looked at the schedule for RailsConf 2024 yet? And are there any workshops on there that you're maybe considering or that maybe have piqued your interest?
STEPHANIE: I have, in fact, and maybe I will check off attending a workshop [laughs] off my bucket list this year. There are two that I'm excited about. Unfortunately, they're both at the same time slot, so I --
JOËL: Oh no. You're going to have to choose.
STEPHANIE: I know. I imagine I'll have to choose. But I'm interested in the Let's Extend Rails With A Gem by Noel Rappin and Vision For Inclusion Workshop run by Todd Sedano. The Rails gem one I'm excited about because it's just something that I haven't had to do really in my dev career so far, and I think I would really appreciate having that guidance. And also, I think that would be motivation to just get that, like, hands-on experience with it. Otherwise, you know, this is something that I could say that I would want to do and then never get [chuckles] around to it.
JOËL: Right, right. And building a gem is the sort of thing that I think probably fits better in a workshop format than in a talk format.
STEPHANIE: Yeah. And I've really appreciated all of Noel's content out there. I've found it always really practical, so I imagine that the workshop would be the same.
JOËL: So, other than poring over the RailsConf schedule and planning your time there, what has been new for you this week?
STEPHANIE: I have a really silly one [laughs].
JOËL: Okay.
STEPHANIE: Which is, yesterday I went out to eat dinner to celebrate my partner's birthday, and I experienced, for the first time, robots [laughter] at this restaurant. So, we went out to Hot Pot, and I guess they just have these, like, robot, you know, little, small dish delivery things. They were, like, as tall as me, almost, at least, like, four feet. They were cat-themed.
JOËL: [laughs]
STEPHANIE: So, they had, like...shaped like cat...they had cat ears, and then there was a screen, and on the screen, there was, like, a little face, and the face would, like, wink at you and smile.
JOËL: Aww.
STEPHANIE: And I guess how this works is we ordered our food on an iPad, and if you ordered some, like, side dishes and stuff, it would come out to you on this robot cat with wheels.
JOËL: Very fun.
STEPHANIE: This robot tower cat. I'm doing a poor job describing it because I'm still apparently bewildered [laughs]. But yeah, I was just so surprised, and I was not as...I think I was more, like, shocked than delighted. I imagine other people would find this, like, very fun. But I was a little bit bewildered [laughs].
The other thing that was very funny about this experience is that these robots were kind of going down the aisle between tables, and the aisles were not quite big enough for, like, two-way traffic. And so, there were times where I would be, you know, walking up to go use the restroom, and I would turn the corner and find myself, like, face to face with one of these cat robot things, and, like, it's starting to go at me. I don't know if it will stop [laughs], and I'm the kind of person who doesn't want to find out.
JOËL: [laughs]
STEPHANIE: So, to avoid colliding with this, you know, food delivery robot, I just, like, ran away from it [laughs].
JOËL: You don't know if they're, like, programmed to yield or something like that.
STEPHANIE: Listen, it did not seem like it was going to stop.
JOËL: [laughs]
STEPHANIE: It got, like, I was, you know, kind of standing there frozen in paralysis [laughs] for a little while. And then, once it got, I don't know, maybe two or three feet away from me, I was like, okay, like, this is too close for comfort [laughs]. So, that was my, I don't know, my experience at this robot restaurant. Definitely starting to feel like I'm in the, I don't know, is this the future? Someone, please let me know [laughs].
JOËL: Is this a future that you're excited or happy about, or does this future seem a little bit dystopian to you?
STEPHANIE: I was definitely alarmed [laughter]. But I'm not, like, a super early adopter of new technology. These kinds of innovations, if you will, always surprise me, and I'm like, oh, I guess this is happening now [laughs]. And I will say that the one thing I did not enjoy about it is that there was not enough room to go around this robot. It definitely created just pedestrian traffic issues. So, perhaps this could be very cool and revolutionary, but also, maybe design robots for humans first.
JOËL: Or design your dining room to accommodate your vision for the robots. I'm sure that flying cars and robots will solve all of this, for sure.
STEPHANIE: Oh yeah [laughter]. Then I'll just have to worry about things colliding above my head.
JOËL: And for the listeners who cannot see my face right now, that was absolutely sarcasm [laughs]. Speaking of our listeners, today we're going to look at a group of different listener questions. And if you didn't know that, you could send in a question to have Stephanie and I discuss, you can do that. Just send us an email at hosts@bikeshed.fm. And sometimes, we put it into a regular episode. Sometimes, we combine a few and sort of make a listener question episode, which is what we're doing today.
STEPHANIE: Yeah. It's a little bit of a grab bag.
JOËL: Our first question comes from Yuri, and Yuri actually has a few different questions. But the first one is asking about Episode 349, which is pretty far back. It was my first episode when I was coming on with Chris and Steph, and they were sort of handing the baton to me as a host of the show. And we talked about a variety of hot takes or unpopular opinions.
Yuri mentions, you know, a few that stood out to him: one about SPAs being not so great, one about how you shouldn't need to have a side project to progress in your career as a developer, one about developer title inflation, one about DRY and how it can be dangerous for a mid-level dev, avoiding let in RSpec specs, the idea that every if should come with an else, and the idea that developers shouldn't be included in design and planning. And Yuri's question is specifically the question about if statements, that every if should come with an else. Is that still an opinion that we still have, and why do we feel that way?
STEPHANIE: Yeah, I'm excited to get into this because I was not a part of that episode. I was a listener back then when it was still Steph and Chris. So, I am hopefully coming in with a different, like, additional perspective to add as well while we kind of do a little bit of a throwback. So, the one about every if should come with an else, that was an unpopular opinion of yours. Do you mind kind of explaining what that means for you?
JOËL: Yeah. So, in general, Ruby is an expression-oriented language. So, if you have an if that does not include an else, it will implicitly return nil, which can burn you. There may be some super expert programmers out there that have never run into undefined method for nil nil class, but I'm still the kind of programmer who runs into that every now and then. And so, implicit nils popping up in my code is not something I generally like. I also generally like having explicit else for control flow purposes, making it a little bit clearer where flow of control goes and what are the actual paths through a particular method.
And then, finally, doing ifs and elses instead of doing them sort of inline or as trailing conditionals or things like that, by having them sort of all on each lines and balancing out. The indentation itself helps to scan the code a little bit more. So, deeper indentation tells you, okay, we're, like, nesting multiple conditions, or something like that. And so, it makes it a little bit easier to spot complexity in the code. You can apply, and I want to say this is from Sandi Metz, the squint test.
STEPHANIE: Yeah, it is.
JOËL: Where you just kind of, like, squint at your code so you're not looking at the actual characters, and more of the structure, and the indentation is actually a friend there rather than something to fight. So, that was sort of the original, I think, idea behind that. I'm curious, in your experience, if you would like to balance your conditionals, ifs with something else, or if you would like to do sort of hanging ifs.
STEPHANIE: Hanging ifs, I like that phrase that you just coined there. I agree with your opinion, and I think it's especially true if you're returning values, right? I mean, in Ruby, you kind of always are. But if you are caring about return values, like you said, to avoid that implicit nil situation, I find, especially if you're writing tests for that code, it's really easy, you know, if you spot that condition, you're like, okay, great. Like, this is a path I need to test.
But then, oftentimes, you don't test that implicit path, and if you don't enter the condition, then what happens, right? So, I think that's kind of what you're referring to when you talk about both. It's, like, easier to spot in terms of control flow, like, all the different paths of execution, as well as, yeah, like, saving you the headaches of some bugs down the line.
One thing that I thought about when I was kind of revisiting that opinion of yours is the idea of like, what are you trying to communicate is different or special about this condition when you are writing an if statement? And, in my head, I kind of came up with a few different situations you might find yourself in, which is, one, where you truly just have, like, a special case, and you're treating that completely differently. Another when you have more of a, like, binary situation, where it's you want to kind of highlight either...more of a dichotomy, right? It's not necessarily that there is a default but that these are two opposite things. And then, a third situation in which you have multiple conditions, but you only happen to have two right now.
JOËL: Interesting. And do you think that, like, breaking down those situations would lead you to pick different structures for writing your conditionals?
STEPHANIE: I think so.
JOËL: Which of those scenarios do you think you might be more likely to reach for an if that doesn't have an else that goes with it?
STEPHANIE: I think that first one, the special case one. And in Yuri's email, he actually asked, as a follow-up, "Do we avoid guard clauses as a result of this kind of heuristic or rule?" And I think that special case situation is where a guard clause would shine because you are highlighting it by putting it at the top of a method, and then saying like, you know, "Bail out of this" or, like, "Return this particular thing, and then don't even bother about the rest of this code."
JOËL: I like that. And I think guard clauses they're not the first thing I reach for, but they're not something I absolutely avoid. I think they need to be used with care. Like you said, they have to be in the top of your method. If you're adding returns and things that break out of your method, deep inside a conditional somewhere, 20 lines into your method, you don't get to call that a guard clause anymore. That's something else entirely. I think, ideally, guard clauses are also things that will break out of the method, so they're maybe raising exception. Maybe they're returning a value. But they are things that very quickly check edge cases and bail so that the body of the method can focus on expecting data in the correct shape.
STEPHANIE: I have a couple more thoughts about this; one is I'm reminded of back when we did that episode on kind of retroing Sandi Metz's Rules For Developers. I think one of the rules was: methods should only be five lines of code. And I recall we'd realized, at least I had realized for the first time, that if you write an if-else condition in Ruby, that's exactly five lines [laughs].
And so, now that I'm thinking about this topic, it's cool to see that a couple of these rules converge a little bit, where there's a bit of explicitness in saying, like, you know, if you're starting to have more conditions that can't just be captured in a five-line if-else statement, then maybe you need something else there, right? Something perhaps like polymorphic or just some way to have branched earlier.
JOËL: That's true. And so, even, like, you were talking about the exceptional edge cases where you might want to bail. That could be a sign that your method is doing too much, trying to like, validate inputs and also run some sort of algorithm. Maybe this needs to be some sort of, like, two-step thing, where there's almost, like, a parsing phase that's handled by a different object or a different method that will attempt to standardize your inputs and raise the appropriate errors and everything. And then, your method that has the actual algorithm or code that you're trying to run can just assume that its inputs are in the correct shape, kind of that pushing the uncertainty to the edges.
And, you know, if you've only got one edge case to check, maybe it's not worth to, like, build this in layers, or separate out the responsibilities, or whatever. But if you're having a lot, then maybe it does make sense to say, "Let's break those two responsibilities out into two places."
STEPHANIE: Yeah. And then, the one last kind of situation I've observed, and I think you all talked about this in the Unpopular Opinions episode, but I'm kind of curious how you would handle it, is side effects that only need to be applied under a certain condition. Because I think that's when, if we're focusing less on return values and more just on behavior, that's when I will usually see, like, an if something, then do this that doesn't need to happen for the other path.
JOËL: Yes. I guess if you're doing some sort of side effect, like, I don't know, making a request to an API or writing to a file or something, having, like, else return nil or some other sentinel value feels a little bit weird because now you're caring about side effects rather than return values, something that you need to keep thinking of. And that's something where I think my thing has evolved since that episode is, once you start having multiple of these, how do they compose together? So, if you've got if condition, write to a file, no else, keep going. New if condition, make a request to an API endpoint, no else, continue.
What I've started calling independent conditions now, you have to think about all the different ways that they can combine, and what you end up having is a bit of a combinatorial explosion. So, here we've got two potential actions: writing to a file, making a request to an API. And we could have one or the other, or both, or neither could happen, depending on the inputs to your method, and maybe you actually want that, and that's cool.
Oftentimes, you didn't necessarily want all of those, especially once you start going to three, four, five. And now you've got that, you know, explosion, like, two to the five. That's a lot of paths through your method. And you probably didn't really need that many. And so, that can get really messy. And so, sometimes the way that an if and an else work where those two paths are mutually exclusive actually cuts down on the total number of paths through your method.
STEPHANIE: Hmm, I like that. That makes a lot of sense to me. I have definitely seen a lot of, like, procedural code, where it becomes really hard to tell how to even start relating some of these concepts together. So, if you happen to need to run a side effect, like writing to a file or, I don't know, one common one I can think of is notifying something or someone in a particular case, and maybe you put that in a condition. But then there's a different branching path that you also need to kind of notify someone for a similar reason, maybe even the same reason.
It starts to become hard to connect, like, those two reasons. It's not something that, like, you can really scan for or, like, necessarily make that connection because, at that point, you're going down different paths, right? And there might be other signals that are kind of confusing things along the way. And it makes it a lot harder, I think, to find a shared abstraction, which could ultimately make those really complicated nested conditions a little more manageable or just, like, easier to understand at a certain complexity. I definitely think there is a threshold.
JOËL: Right. And now you're talking about nested versus non-nested because when conditions are sort of siblings of each other, an if-else behaves differently from two ifs without an else. I think a classic situation where this pops up is when you're structuring code for a wizard, a multi-step form. And, oftentimes, people will have a bunch of checks. They're like, oh, if this field is present, do these things. If this field is present, do these things.
And then, it becomes very tricky to know what the flow of control is, what you can expect at what moment, and especially which actions might get shared across multiple steps. Is it safe to refactor in one place if you don't want to break step three? And so, learning to think about the different paths through your code and how different conditional structures will impact that, I think, was a big breakthrough for me in terms of taking the next logical step in terms of thinking, when do I want to balance my ifs and when do I not want to? I wrote a whole article on the topic. We'll link it in the show notes.
So, Yuri, thanks for a great question, bringing us back into a classic developer discussion. Yuri also asks or gives us a bit of a suggestion: What about revisiting this topic and doing an episode on hot takes or unpopular topics? Is that something that you'd be interested in, Stephanie?
STEPHANIE: Oh yeah, definitely, because I didn't get to, you know, share my hot topics the last episode [laughs]. [inaudible 24:23]
JOËL: You just got them queued up and ready to go.
STEPHANIE: Yeah, exactly. So, yeah, I will definitely be brainstorming some spicy takes for the show.
JOËL: So, Yuri, thanks for the questions and for the episode suggestion.
STEPHANIE: So, another listener, Kevin, wrote in to us following up from our episode on Module Docs and about a different episode about Multi-dimensional Numbers. And he mentioned a gem that he maintains. It's called Ruby Units. And it basically handles the nitty gritty of unit conversions for you, which I thought was really neat.
He mentioned that it has a numeric class, and it knows how to do math [laughs], which I would find really convenient because that is something that I have been grateful not to have to really do since college [laughs], at least those unit conversions and all the things that I'd probably learned in math and physics courses [laughs]. So, I thought that was really cool, definitely is one to check out if you frequently work with units. It seemed like it would be something that would make sense for a domain that is more science or deals in that kind of domain.
JOËL: I'm always a huge fan of anything that tags raw numbers that you're working with with a quantity rather than just floating raw numbers around. It's so easy to make a mistake to either treat a number as a quantity you didn't think of, or make some sort of invalid operation on it, or even to think you have a value in a different size than you do. You think you're dealing with...you know you have a time value, but you think it's in seconds. It's actually in milliseconds. And then, you get off by some big factor.
These are all mistakes that I have personally made in my career, so leaning on a library to help avoid those mistakes, have better information hiding for the things that really aren't relevant to the work that I'm trying to do, and also, kind of reify these ideas so that they have sort of a name, and they're, like, their own object, their own thing that we can interact with in the app rather than just numbers floating around, those are all big wins from my perspective.
STEPHANIE: I also just thought of a really silly use case for this that is, I don't know, maybe I'll have to experiment with this. But every now and then, I find the need to have to convert a unit, and I just pop into Google, and I'm like, please give me, you know, I'll search for 10 kilometers in miles or something [laughs]. But then I have to...sometimes Google will figure it out for me, and sometimes it will just list me with a bunch of weird conversion websites that all have really old-school UI [laughs]. Do you know what I'm talking about here?
Anyway, I would be curious to see if I could use this gem as a command-line interface [laughs] for me without having to go to my browser and roll the dice with freecalculator.com or something like that [laughs].
JOËL: One thing that's really cool with this library that I saw is the ability to define your own units, and that's a thing that you'll often encounter having to deal with values that are maybe not one of the most commonly used units that are out there, dealing with numbers that might mean a thing that's very particular to your domain. So, that's great that the library supports that. I couldn't see if it supports multi-dimensional units. That was the episode that inspired the comment. But either way, this is a really cool library. And thank you, Kevin, for sharing this with us.
STEPHANIE: Kevin also mentions that he really enjoys using YARD docs. And we had done that whole episode on Module Docs and your experience writing them. So, you know, your people are out there [laughs].
JOËL: Yay.
STEPHANIE: And we talked about this a little bit; I think that writing the docs, you know, on one hand, is great for future readers, but, also, I think has the benefit of forcing the author to really think about their inputs and outputs, as Kevin mentions. He's found bugs by simply just going through that process in designing his code, and also recommends Solargraph and Solargraph's VSCode extension, which I suspect really kind of makes it easy to navigate a complex codebase and kind of highlight just what you need to know when working with different APIs for your classes. So, I recently kind of switched to the Ruby LSP, build with Shopify, but I'm currently regretting it because nothing is working for me right now. So, that might be the push that I need [laughs] to go back to using Solargraph.
JOËL: It's interesting that Kevin mentions finding bugs while writing docs because that has absolutely been my experience. And even in this most recent round, I was documenting some code that was just sort of there. It wasn't new code that I was writing. And so, I had given myself the rule that this would be documentation-only PRs, no code changes. And I found some weird code, and I found some code that I'm 98% sure is broken.
And I had to have the discipline to just put a notice in the documentation to be like, "By the way, this is how the method should work. I'm pretty sure it's broken," and then, maybe come back to it later to fix it. But it's amazing how trying to document code, especially code that you didn't write yourself, really forces you to read it in a different way, interact with it in a different way, and really, like, understand it in a deep way that surprised me a little bit the first time I did it.
STEPHANIE: That's cool. I imagine it probably didn't feel good to be like, "Hey, I know that this is broken, and I can't fix it right now," but I'm glad you did. That takes a lot of, I don't know, I think, courage, in my opinion [laughs], to be like, "Yeah, I found this, and I'm going to, you know, like, raise my hand acknowledging that this is how it is," as supposed to just hiding behind a broken functionality that no one [laughs] has paid attention to.
JOËL: And it's a thing where if somebody else uses this method and it breaks in a way, and they're like, "Well, the docs say it should behave like this," that would be really frustrating. If the docs say, "Hey, it should behave like this, but it looks like it's broken," then, you know, I don't know, I would feel a little bit vindicated as a person who's annoyed at the code right now.
STEPHANIE: For sure.
JOËL: Finally, we have a message from Tim about using Postgres' EXPLAIN ANALYZE. Tim says, "Hey, Joël, in the last episode, you talked a bit about PG EXPLAIN ANALYZE. As you stated, it's a great tool to help figure out what's going on with your queries, but there is a caveat you need to keep in mind. The query planner uses statistics gathered on the database when making decisions about how to fetch records. If there's a big difference between your dev or staging database and production, the query may make different decisions.
For example, if a table has a low number of records in it, then the query planner may just do a table scan, but in production, it might use an index. Also, keep in mind that after a schema changes, it may not know about new indexes or whatever unless an explicit ANALYZE is done on the table." So, this is really interesting because, as Tim mentions, EXPLAIN ANALYZE doesn't behave exactly the same in production versus in your local development environment.
STEPHANIE: When you were trying to optimize some slow queries, where were you running the ANALYZE command?
JOËL: I used a combination. I mostly worked off of production data. I did a little bit on a staging database that had not the same amount of records and things. That was pretty significant. And so, I had to switch to production to get realistic results. So, yes, I encountered this kind of firsthand.
STEPHANIE: Nice. For some reason, this comment also made me think of..., and I wanted to plug a thoughtbot shell command that we have called Parity, which lets you basically download your production database into your local dev database if you use Heroku. And that has come in handy for me, obviously, in regular development, but would be really great in this use case.
JOËL: With all of the regular caveats around security, and PII, and all this stuff that come with dealing with production data. But if you're running real productions on production, you should be cleared and, like, trained for access to all of that. I also want to note that the queries that you all worked with on Friday are also from the production database.
STEPHANIE: Really?
JOËL: So, you got to see what it actually does, what the actual timings were.
STEPHANIE: I'm surprised by that because we were using, like, a web-based tool to visualize the query plans. Like, what were you kind of plugging into the tool for it to know?
JOËL: So, the tool accepts a query plan, which is a text output from running a SQL query.
STEPHANIE: Okay. So, it's just visualizing it.
JOËL: Correct. Yeah. So, you've got this query plan, which comes back as this very intimidating block of, like, text, and arrows, and things like that. And you plug it into this web UI, and now you've got something that is kind of interactive, and visual, and you can expand or collapse nodes. And it gives you tooltips on different types of information and where you're spending the most time. So, yeah, it's just a nicer way to visualize that data that comes from the query plan.
STEPHANIE: Gotcha. That makes sense.
JOËL: So, that's a very important caveat. I don't think that's something that we mentioned on the episode. So, thank you, Tim, for highlighting that. And for all of our listeners who were intrigued by leaning into EXPLAIN ANALYZE and query plan viewers to debug your slow queries, make sure you try it out in production because you might get different results otherwise.
STEPHANIE: So, yeah, that about wraps up our listener topics in recent months. On that note, Joël, shall we wrap up?
JOËL: Let's wrap up.
STEPHANIE: Show notes for this episode can be found at bikeshed.fm.
JOËL: This show has been produced and edited by Mandy Moore.
STEPHANIE: If you enjoyed listening, one really easy way to support the show is to leave us a quick rating or even a review in iTunes. It really helps other folks find the show.
JOËL: If you have any feedback for this or any of our other episodes, you can reach us @_bikeshed, or you can reach me @joelquen on Twitter.
STEPHANIE: Or reach both of us at hosts@bikeshed.fm via email.
JOËL: Thanks so much for listening to The Bike Shed, and we'll see you next week.
ALL: Byeeeeeeeee!!!!!!!
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