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by Jiří {x2} Činčura

JavaDays 2017

16 Oct 2017 Presentations & Speaking

Stejně jako .NET, Microsoft a techonologie kolem mají výbornou Gopas TechEd konferenci, má i Java svět svoji - JavaDays. Letos se uskuteční 13. - 14. listopadu a já jsem si připravil několik přednášek, které vás doufám zaujmou. Především kolem tématu databází, které je mi velmi blízké.

Playing with asyncio and aiohttp in Python as a C# developer

12 Oct 2017 Multithreading/Parallelism/Asynchronous/Concurrency, Python

Few months back I decided to play a little with asyncio in Python. Explore a little bit how “they did it” and align that in my mind with what I know about the implementation in .NET. Because at that time I needed some HTTP probing I decided to test the async IO together with regular HTTP (aka network) requests. And I used aiohttp. Not that I did some big research. I did quick search and looked at some demos to see whether I like how it’s structured or not. And aiohttp felt fine.

Comparing speed of “Count > 0” and “Any”

29 Sep 2017 .NET, C#, LINQ

I hate seeing Count > 0 when doing code reviews. And I always recommend using Any instead. It shows the intention, hence makes the code more readable, I think.

Although I would always choose readability over performance - unless in some very specific cases, with well-defined numbers - at one point I wondered whether there’s a cost in using Any. Speed? Allocations?

Konference CORESTART 2.0

20 Sep 2017 Presentations & Speaking

Letošní CORESTART 2.0 (2. - 3. listopadu) naváže na loňskou “edici“, tentokrát samozřejmě se zaměřením na .NET Core 2.0 a všeho okolo něj. Verze 2.0 už opravdu něco umí a jde na ní solidně stavět. Kromě zahraničních speakerů, přispěji i já svou troškou do mlýna dvěma přednáškami - jedna kolem Entity Frameworku Core 2.0 a druhá kolem novinek v C# 7 a dál. Novinek je hodně a program stojí za to. Přijďte, nebudete litovat.

Purple squiggle in Visual Studio

8 Sep 2017 Visual Studio

I’m pretty sure you know what the red squiggle in Visual Studio means (correct, it’s the error). Very likely you know green squiggle (correct, it’s the warning). Maybe you know blue squiggle (correct, it’s the message). But do you know what purple squiggle means? By the way the official name for squiggle in Visual Studio is wavy underline.

Run To Cursor in Call Stack window

7 Sep 2017 Visual Studio

Today I found a great new feature for debugging in Visual Studio. Maybe you know the Run to Cursor feature (if not, I’ll explain it in next paragraph), but did you know you can use the same feature from Call Stack as well?

My kind of Jekyll copy written in .NET

30 Aug 2017 .NET, C#, Hugo, Jekyll, Pelican, Ruby

Last couple of years I published this blog using Jekyll. Static pages are hard to beat in performance and security. Initially on GitHub pages, then GitLab Pages and eventually moving to Azure. Mainly because thanks to web.config I have more control over the webserver (IIS) and I can do bit more (in fact quite a lot). But lately I started to be more and more tired of Jekyll. It was slow for me and given it’s a Ruby application and me not being fan nor fluent of Ruby it started to add up. For maybe a year I looked multiple times at Hugo, because it was an obvious choice and didn’t liked the templating structure. Also Pelican, because it’s written in Python and I like Python. Not sure why, but I didn’t convert to it. And I also played multiple times with the idea of writing something myself, just to dismiss that idea hundred times because I knew I would trap myself in constantly fiddling with it and burning my free time.

ADO.NET provider for Firebird is ready (with .NET Standard 2.0 support)

30 Aug 2017 .NET, .NET Standard, C#, Databases in general, Entity Framework, Entity Framework Core, Entity SQL, Firebird, LINQ, SQL, Visual Studio

New version of ADO.NET provider for Firebird is ready for download. This release is about .NET Standard 2.0. Now the .NET Standard 2.0, with all the new APIs supported, version is available (this work, together with upcoming Entity Framework Core 2.0 support, is sponsored by Integrative9).

Another new feature is support for passing key over the wire for encrypted databases (you need to have server side plugin for this feature, i.e. this from IBPhoenix). New connection string property crypt key is available for that. The value is base64 encoded data representing the key. You can find small example in tests.

ADO.NET provider for Firebird is ready

25 Aug 2017 .NET, C#, Databases in general, Entity Framework, Entity SQL, Firebird, LINQ, SQL, Visual Studio

New version of ADO.NET provider for Firebird is ready for download. Apart from regular bugfixes some new features are available. Notably, FbTrace now supports new format of Firebird 3 and then DefaultFbMigrationSqlGeneratorBehavior allows easier customization in case you want specific behavior for Entity Framework Migrations.

Using string interpolation for ADO.NET parameters

16 Aug 2017 C#, SQL

I was reading the announcement about Entity Framework Core 2 the other morning and saw “String interpolation in raw SQL methods” paragraph. This was already in preview(s) and I kind of took it as granted, not thinking about how it’s done or what it is doing. Not this time. Somehow my curiosity kicked in and I decided to create same feature and maybe do something with it.

Of course, I could peek into sources, but I decided to use the idea, but build it myself from scratch. I like the idea of using already existing feature from C# and then using for different, but reasonable, purpose. String interpolation and SQL parameters are exactly this.

Replacing assembly while the application is running (aka AppDomains are slow)

25 Jul 2017 .NET, C#

As I said in previous post I had to drop AppDomains from my solution to allow replacing assembly while the FbNetExternalEngine is running. Calls across AppDomains are simply too slow (read: I can’t make it fast enough. 😉) for this kind of project. Why I even needed AppDomains? The specs are simple: Allow assembly replacing (rewrite) while it’s loaded in Firebird via my FbNetExternalEngine. Can it be solved without AppDomains?

FbNetExternalEngine performance numbers

24 Jul 2017 .NET, Firebird

Over the last few days I was working on performance of FbNetExternalEngine. Basically doing all I can to make it execute the code quickly as possible. OK, maybe not all I can, but something that gives biggest gain while being able to program it in a reasonable timeframe, because there’s always room for more.