By default, SQL Server 0’s out database files as it allocates space for them. This can be good for security/reliability in a production environment, but it means SQL Server is writing a bunch of extra data. Turn on instant file initialization in dev/stage/test environments for dramatically faster database creation and backup/restore operations.

There’s no switch for this in SQL Server, strangely enough. To get instant file initialization enabled, you’ve got to grant the “Perform volume maintenance tasks” permission to the SQL Server service account.

Brad McGehee’s got a great detailed analysis of what happens with instant file initialization and walkthrough steps with screenshots.

Microsoft’s Dynamic Linq library has been floating around the internet in one form or another for years. Its been distributed as a raw .cs file, not a NuGet or any sort of supported package. The most central location I’ve found for this is King Wilder’s System.Dynamic.Linq GitHub repo and NuGet package.

I needed support for a couple of things that weren’t included in the original version, namely Sum/Average/Min/Max functions, and that in a dynamically callable way. So I built that, cribbing off of a Sum function found on StackOverflow. The code takes the name of the function you want to call and the name of the property you want to aggregate. It then uses reflection to grab the extension method of the correct type based on the property type you specify and executes it against the IQueryable, returning the result.

After a bit of jiggering, I realized that Sum and Average have totally different signatures than Min/Max for some reason. Adding in separate branches to the code did the trick and I came up with:

/// <summary>
/// Dynamically runs an aggregate function on the IQueryable.
/// </summary>
/// <param name="source">The IQueryable data source.</param>
/// <param name="function">The name of the function to run. Can be Sum, Average, Min, Max.</param>
/// <param name="member">The name of the property to aggregate over.</param>
/// <returns>The value of the aggregate function run over the specified property.</returns>
public static object Aggregate(this IQueryable source, string function, string member)
{
    if (source == null) throw new ArgumentNullException("source");
    if (member == null) throw new ArgumentNullException("member");

    // Properties
    PropertyInfo property = source.ElementType.GetProperty(member);
    ParameterExpression parameter = Expression.Parameter(source.ElementType, "s");
    Expression selector = Expression.Lambda(Expression.MakeMemberAccess(parameter, property), parameter);
    // We've tried to find an expression of the type Expression<Func<TSource, TAcc>>,
    // which is expressed as ( (TSource s) => s.Price );

    var methods = typeof(Queryable).GetMethods().Where(x => x.Name == function);

    // Method
    MethodInfo aggregateMethod = typeof(Queryable).GetMethods().SingleOrDefault(
        m => m.Name == function
            && m.ReturnType == property.PropertyType // should match the type of the property
            && m.IsGenericMethod);

    // Sum, Average
    if (aggregateMethod != null)
    {
        return source.Provider.Execute(
            Expression.Call(
                null,
                aggregateMethod.MakeGenericMethod(new[] { source.ElementType }),
                new[] { source.Expression, Expression.Quote(selector) }));
    }
    // Min, Max
    else
    {
        aggregateMethod = typeof(Queryable).GetMethods().SingleOrDefault(
            m => m.Name == function
                && m.GetGenericArguments().Length == 2
                && m.IsGenericMethod);

        return source.Provider.Execute(
            Expression.Call(
                null,
                aggregateMethod.MakeGenericMethod(new[] { source.ElementType, property.PropertyType }),
                new[] { source.Expression, Expression.Quote(selector) }));
    }
}

I've submitted a pull request with this function to kahnau's repo, and he seems pretty responsive about accepting pull requests, so this will likely be in that NuGet soon.

Software is a unique industry because it is constantly self-improving its own productivity. It acts as an accelerating concept like interchangeable parts or the assembly line, rather than a linear incrementing body of study. The use of software applies that acceleration to everywhere it is used, including itself.

So why don't we have lower skilled people building software by drag/dropping building blocks as many have predicted? After all, we have that self accelerating improvement applied to software over decades. Exponential increases in programmer productivity would suggest that lower skilled people could be employed, dropping average salaries, right? That kind of logic leads toward thinking there is a tech worker shortage.

There is no "tech worker shortage". Companies might not be able to find low priced labor, which they believe they should be able to do based on the reasoning above. But like the linked article quotes: "I'm not sure that qualifies as a shortage, any more than my not being able to find a half-priced TV."

What's wrong with this train of thought?

First off, there are many "building block" type software packages available. It's just hard to see them because the demand for new and more complex software has grown so dramatically. There are website builders, time tracking software, component based development tools galore. They've satisfied an enormous amount of what people wanted to do 20 years ago. But in the meantime, demand and complexity of requirements have grown exponentially. The acceleration of productivity is just barely allowing the software industry to run in place.

At the same time, there is an increasing demand for custom built software that is tailored directly to the data and business logic of the client, particularly in the LOB arena. It used to be too expensive for anything other than massive companies to afford custom development. Now, productivity increases allow even small businesses to have staff or contract programmers building software to enhance their business, again, pushing demand for programmers back up.

Finally, and most importantly, software is getting more complex in general. The requirements are bigger, in features, volume, and reliability. The software enabling productivity increases is sitting on layer upon layer of other software packages. 20 years ago, you'd build a simple desktop app in C++ or VB. Or a CGI app for web. It'd be a couple of components, sitting on a single server (or maybe a cluster of two machines if you were really rich and important), with a simple database. The "cloud" was still a twinkle in Jeff Bezos's eye until less than 10 years ago. Now, you have an MVC app using 20 different packages imported by a package manager running on a load balanced set of web servers, a database sharded across several servers, some memcache servers on the backend to accelerate data access, some varnish caches on the front to accelerate static pages, some CDN to accelerate content. Etcetera etcetera.

A senior software engineer that knows all of the possible tools and can orchestrate them together, someone that knows the concepts from the underlying cpu/cache/memory up to the networked cloud, and can use the right tool (out of 100s) for the right job, getting the job done (not to mention done right, and done fast) -- that person's value and productivity is multiplied by the layer upon layer of tooling developed over the past couple of decades. They can do the work that 10 senior people did 10 or 15 years ago, or 100 junior devs, while the junior dev's productivity has remained about the same.

That dichotomy between productivity of a senior and junior is what is throwing big companies for a loop. Their mental model of staffing is hierarchical, with a couple of seniors at the top, then some mids, and a bunch of juniors filling out the crowd. Their sort of thinking around cost is what leads to outsourcing to low skilled body shops. They can't fathom that it would be cheaper and more effective to hire a bunch of seniors and a couple mids to get the job done right -- they just see the dollar signs on the salary packages and scream "tech shortage".

Software development is becoming another market with winner-take-all dynamics. Sure, anybody can get started easy and for free. But the thousands of hours invested over years that it takes to gain an innate understanding of the innumerable tools and techniques involved? That’s another matter entirely.

I just finished building and setting up my first Home Theater PC. It went very smoothly. I didn’t run into any of the typical config issues of yore when installing the machine -- driver issues, incompatible hardware, etc. Everything pretty much just worked. Of course, I didn't get into the hard part of HTPC -- handling live TV. I'm on DirecTV right now, and there's no way I'm aware of to do live TV on a PC with them. No CableCARD support, etc. And CableCARD just got shot down in congress anyway, so we'll see how long it lasts elsewhere.

Cute little thing, ain't it?

Hardware:

• Gigabyte BRIX 4770R
• 16 GB RAM
• 240 GB mSATA SSD
• Logitech K830 keyboard
• Wireless Windows 360 controller kit
• Windows Media Center/RC6 IR remote kit

Software:

• Windows 8.1 Pro
• Windows Media Center
• Plex
• XBMC (now Kodi)
• Steam Big Picture mode

One note on Windows Media Center – if you decide you want that, just go ahead and buy the key online for $9.99. It’s ten bucks. Don’t try to find a working key somewhere like I did. It’ll appear to work, but it’ll bounce Windows into deactivated mode. And then Windows won’t let you downgrade and also won’t let you buy a key. Most people suggest just reinstalling at that point. I was able to sidestep the issue by buying a key on a different machine and applying it back on my HTPC. MS tech support aren’t very supportive either, as they assume you’re trying to pull some shenanigans. Be forewarned.

I typed out this entire post on the HTPC, looking at my TV and using the K830 keyboard. It’s surprisingly comfortable and usable, with big fat keys and fairly responsive key travel. The built in touchpad is brilliant -- you can easily mouse around without having to dig through the couch for a mouse.

My goals for this setup are:

• Be able to easily consume my recorded media from the TV. You can sort of do this with streaming to a 360, maybe with a TVersity server in back, but it’s fiddly.
• Hook in cloud streaming apps like Netflix, Pandora, etc. so they can be used as well
• Play Steam games that support the controller on the TV
• Full browser and potential for other apps in case I want to look up something, or do stuff like write this blog post

I’ve satisfied the basic requirements of these goals, but I’m a little disappointed in the lack of ability to do advanced orchestration. I haven’t found a way to do everything from one UI/app yet, or be able to do everything from the remote. Ironically enough, the best integrated things are the less than legitimate options. The paid apps like Netflix all wall themselves off in their own little gardens and don’t play with others.

Tweaks I did:

• Create a guest account and run all TV apps as a guest. This opens the HTPC up to everybody without worrying that somebody is going to screw things up or install a virus.
• Registry changes to auto logon guest account:

  HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
  AutoAdminLogon = REG_SZ 1
  DefaultPassword = ""
  DefaultUsername = "Guest"

• Registry changes to disable lock screen:

  HKLM\SOFTWARE\Policies\Microsoft\Windows\Personalization
  NoLockScreen = 1

• Don't require password on resume
  • Go to Power Options control panel applet
  • Click on "Require Password on Wakeup" on the left pane
  • Select the option "Don't require a password"
• Change the guest profile picture to something good looking by overwriting guest.bmp and guest.png in C:\ProgramData\Microsoft\User Account Pictures
• Add the unsupported appstore to Plex for access to unsavory and pirate stream content
• Run plex as a service (thanks to http://cloudsurvivalguide.com/running-plex-service-windows/)
  • Set up plex server as you want it on your account or some other user account
  • When set up, remove it as a startup app (look in HKCU\Software\Microsoft\Windows\CurrentVersion\Run)
  • Install Windows 2003 Resource Kit to get srvany.exe. This app will let you run any other app as a Windows Service.
  • Execute the following in a Admin command prompt and/or .bat file to create the service:

    sc create Plex binpath= "C:\Program Files (x86)\Windows Resource Kits\Tools\srvany.exe" start= "auto" DisplayName= "Plex Media Server"
    
    REG ADD HKLM\SYSTEM\CurrentControlSet\Services\Plex\Parameters
    REG ADD HKLM\SYSTEM\CurrentControlSet\Services\Plex\Parameters /v AppDirectory /t REG_SZ /d "C:\Program Files (x86)\Plex\Plex Media Server"
    REG ADD HKLM\SYSTEM\CurrentControlSet\Services\Plex\Parameters /v Application /t REG_SZ /d "C:\Program Files (x86)\Plex\Plex Media Server\Plex Media Server.exe"
    
    Net Start Plex

  • Go into the local Services settings and open Plex properties. Change the user in the Log On tab to point to the user you used to set up plex

I spent some time looking for a simple compound interest calculation function in .NET today. I couldn't find anything usable, so I grabbed the source formula and reduced it to .NET.

Here's the formula:

A = P * (1 + r / n) ^ n * t
A = final total amount
P = principal amount
r = interest rate (decimal)
n = number of periods per year
t = number of years

The C# code:

decimal CalculateTotalWithCompoundInterest(decimal principal, decimal interestRate, int compoundingPeriodsPerYear, double yearCount)
{
    return principal * (decimal)Math.Pow((double)(1 + interestRate / compoundingPeriodsPerYear), compoundingPeriodsPerYear * yearCount);
}

For example, you can calculate the total loan amount for $10,000.00 (principal and interest), compounded daily for 2 years like so:

decimal total = CalculateTotalWithCompoundInterest(10000m, 8.5m, 365, 2);