Find or Where

January 27, 2025

I'm doing dotnet development for eight years, but just today I finally realised, what is the difference between .Find(..) and .Where(..):
When Where always makes request to database, Find looks first by id in already cached entities and only if not found, checks in database.
I must have read about it previously, but only today I have found that one particularly big chunk of a very important command works accidentally correctly because of that: we make a very big loop, in each iteration we create new entity with id from external source and saving to database happen only afterwards. Would we have used Where, entries would be duplicated (and exception thrown), but with Find it's possible to get cached version, that was not yet saved to database.
Here is small example that demonstrates what I mean:

public record Person(int Id, string Name);

using var db = new AppDbContext();
db.Database.EnsureCreated();

db.Peoples.Add(new Person(60, "John"));

db.Peoples.FirstOrDefault(p => p.Id == 60); // will return null
var jackByFind = db.Peoples.Find(60); // will return entity

It is also possible to make query to cache using DbSet<T>.Local.Where(..), but afaik there is no straightforward way to make complex query by non-key parameters to cached version and, if not found - to database.

Relay 10

July 27, 2024

In a couple of weeks would be ten years since I moved from Russia to Germany. Because of my work I urgently needed to improve my English and someone suggested to me listening to podcasts. Because I was proud owner of macbook air 2013, I quickly found Accidental Tech Podcast and it was so entertaining, that I kept listening to them even I didn’t understand (more than) a half of it. Then I found Analogu(e), then other relay shows and since 2015 they helped me not just learning language and keep up with apple news, but also with my mental health, when I migrated from my homeland country to place where I did not had any friends nor time to find ones. Being tonight on live show felt so surreal to see people, that previously were just voices in my head. And see the community of diverse, helping and engaged people is amazing. Thanks, Mike and Stephen for making this amazing thing and thank everyone involved!

Pgsql timezones

November 3, 2023

It’s been 0️⃣ days since last time I was confused about timezones. Recently I noticed that we store local timezone in our db as timestamp with time zone: 2023-11-03T14:20:00+01:00 instead of UTC time.
When I used switch “Npgsql.EnableLegacyTimestampBehaviour” it seemed, that it saved UTC value into database, but on reading DateTime kind was Local, which was incorrect.
Long story short: I didn’t notice big red warning in Npgsql documentation. When we save UTC to db, it uses local timezone to represent values.
For example, if I change local timezone: SET TIMEZONE ‘Asia/Brunei’ it would show time as 2023-11-03T21:20:00+08:00, but data wouldn’t have changed, only how it displayed on the screen. And it transfers into C# layer properly.
More than that, RFC3339 allows it and states that it is a correct format to display UTC.

Window management

August 18, 2023

On recent episode of Mac Power Users David and Stephen talked about possible solutions for window management on a mac. I have tried many apps for that before and especially last fall, when I switched to using a mac as main working computer. So I want to describe my setup here, not because it would be interesting and/or usefull to anyone, but as reminder for myself for the next time I would need to set up a new macbook.
My main requirements for window management software:

1. it should be controlled completely from keyboard
2. it should be available outside app store (because on working machine I don't have access to that)

Rectangle

This is the main utility. I configured these shortcuts to move windows:
⌃ ⌥ ← left half
⌃ ⌥ → right half
⌃ ⌥ ↑ center half
⌃ ⌥ ⏎ maximize

Best of all, by clicking several times, it switches between windows sizes. For example, clicking ⌃ ⌥ ← first time would move window to the left half of the screen, second time it would resize window, so it still be on the left, but take ⅔ of the screen and third click would resize to ⅓ of the screen. This is extreemly helpful, when I'm using external ultrawide monitor and allows me to arrange windows in just several keyboard clicks. I also set up shortcuts to resize and move windows to sixth parts of the screen, but I use it much less often, usually if I need small terminal panel somewhere on the side. For multimonitor setups there are shortcuts to swap window to next monitor - which is very convenient.

Alt-tab

Another problem in macos after switching from using windows machine is app switcher. I use mac for last decade as personal machine, but usually I dont open many windows or, especially, windows of same application: it's only one browser, one IDE and one terminal. During working hours, I usually have at least three browser windows: one for company apps/tools (jira/github/circleCi etc), one for developed application (different instances of localhost and might be different environment) and third window with google search results. Not because I tend to keep things clean and separated - quite the opposite, every browser has 20-30 tabs open and I would lose everything using one window.
Another example is VS Code - ideally, I work at one project at the time, but quite often I need to run backend and frontend and may be other services in debug mode. Macos default app switcher displays only one icon, selecting exact window can be done with arrow keys. Also, it doesn't show all windows (as example, if there is prerefence window open - it wouldn't be in list of application). Alt-tab app solves this issues, basically bringing windows style app switcher to apple platform.

Using these two apps I can do everything in just couple of keyboard shortcuts, without touching a trackpad (or mouse):

Bonus round

In addition I found many more small utilities.
Sleeve Very customizable UI for currently playing music. I always want to see album cover as well as artist, song title and media controls. Can be placed over other windows, but in this case it's blocking click of big portion of the screen, so I quite often keep it under other windows (left bottom hot corner -> display desktop)
Hyperkey I almost never use capslock. Instead or typing screaming, it can be rebound to ⌃ ⌥ ⌘ ⇧ (aka hyperkey). And then it can be used for global shortcuts. As examle, for me hyperkey + B opens new Bear window and hyperkey + T opens Things
Hidden bar Free and simple alternative to Bartender
Hand mirror Quick check how I look before making any presentation
Hidden menu flags Display country flag in language settings instead of locale.

After moving to mac professionally (second time in my career) I found that any operating sistem is not perfect enough. But there are many mac enthusiasts who are very enthusiastic about making it comfortable for any taste.

WWDC 2023

June 5, 2023

I have revived my blog a couple months ago already, but still have no time or desire to make new posts. Well, just closed wwdc keynode is a good opportunity to finally start typing.
This was a longest  presentation, that I saw and I have no desire to list all products that they preseted, just a couple thoughts:

• 15 inch macbook air looks very interesting for me. If someday I would give up taking my air everywhere I go and in every trip or vacation, then bigger screen is very attractive for home laptop, especially if they would fix resolution issue (hint: do not use default scale on current macbook air). Coding and movie watching can be benefited greatly for additional screen real estate.
• Mood tracking, new meditations and journal app. I'm very curious, how they implemented all of that, however, I doubt, that apple product could ever replace Day one for me.
•  watch widgets. I always struggle between functional watchface that dispay maximum amount of information and minimal face, that looks nice, but doesn't use it's digital nature. Widgets can (in theory) have the best from both worlds - all required information is available from one swipe, but pefectly hidden otherwise. Devil in the details, I would like to see, how usefull it would be.
• Vision Pro? Looks gimmicky, even scary in presentations, where lonely people in empty homes taking swimming glasses and started starring into virtual worlds. I personally don't have any desire to buy such thing, other than to try for fifteen minutes. On the other hand, it is just a first version and not targeted at everyone - my guess, couple years after initial release there would be much improved second version, as it was with watch, with clearer focus and more understanding, how it can be used. It would not overthrow the world in a day, as iPhone did, but I see myself using it in 3-4 years.
  Most interesting part about vision pro - how they render text that way, so it still absolutely readable in VR? If they focused on that, it could be a very unique functionality, that would distinguish apple headset from other VR glasses.