LINQ versus SqlDataReader versus DataSet performance

There is the potential that switching to DataSets rather than business objects will add a significant overhead and adversely affect performance.

• "accessing data through the DataReader is a magnitude of 27-56 times faster than accessing data using the DataSet"
  http://www.devx.com/vb2themax/Article/19887/1954?pf=true

• -------------------------------------------------------------------
  Strongly Typed DataSet Breakdown
  -------------------------------------------------------------------
  175.11% slower than SQL Data Reader
  216.26% faster than LINQ to SQL
  112.17% slower than LINQ to SQL Compiled
  -------------------------------------------------------------------
  

  Performance benchmarks for LINQ vs. SqlDataReader, DataSet - LINQ Compiled Queries: Part 2 http://www.devtoolshed.com/node/12

BitVector32 constructor examples

static void Main(string[] args)
{
    int[] testData = new int[] { 
        int.MinValue, int.MinValue + 1,
        -2, -1, 0, 1, 2, 
        int.MaxValue - 1, int.MaxValue };
    foreach (int test in testData)
    {
        Console.WriteLine(string.Format("{0} -> {1}", test, new BitVector32(test)));
    }

    Console.ReadLine();
}

Outputs:

-2147483648 -> BitVector32{10000000000000000000000000000000}
-2147483647 -> BitVector32{10000000000000000000000000000001}
-2 -> BitVector32{11111111111111111111111111111110}
-1 -> BitVector32{11111111111111111111111111111111}
0 -> BitVector32{00000000000000000000000000000000}
1 -> BitVector32{00000000000000000000000000000001}
2 -> BitVector32{00000000000000000000000000000010}
2147483646 -> BitVector32{01111111111111111111111111111110}
2147483647 -> BitVector32{01111111111111111111111111111111}

So while new BitVector32(-1) may seem a bit odd for a constructor the intention is to set all 32 bits on.

Removing the "warning CS3008: Identifier '__ASP' is not CLS-compliant" warning

I'd been getting "warning CS3008: Identifier '__ASP' is not CLS-compliant" when building a ASP.NET 2.0 website.

Compiler Warning (level 1) CS3008 occurs when:

A public, protected, or protected internal identifier breaks compliance with the Common Language Specification (CLS) if it begins with an underscore character (_).

In my case I was able to remove this warning by changing the CLSCompliantAttribute in the AssemblyInfo.cs of the website.

[assembly: CLSCompliant(false)] //Used to be set to true.

Note: It is a bit odd having an AssemblyInfo.cs for a website. It was linked in using the CompilerOptions property in the masterpage.

Nelson .NET User Group Presentation - Building fast and scalable websites with ASP.NET and SQL Server - 11th of March

Upcoming presentation

Rick Kiessig will be giving a presentation on Wednesday the 11th of March. Rick worked at Microsoft in Silicon Valley for six years as a Solutions Architect, before moving to Nelson two years ago, where he is now working as a consultant.

Title:
Building fast and scalable websites with ASP.NET and SQL Server

Abstract:
Overview of high-impact performance optimization principles that can be applied to all components that affect your website's performance, from the browser to the database. Hear about how browsers process a page and how you can use that information to decrease page load times. Learn how to achieve high-performance, end-to-end caching, along with several tricks that can dramatically improve the performance and scalability of ASP.NET and SQL Server.

Useful links:

• http://mscommunities.net.nz/ - The home of Microsoft communities in New Zealand
• http://www.dot.net.nz/

When:
Wednesday 11th March 2009
Gather at 11:50 am, starting at 12:00 pm.
Approximately 1 hour plus pizza afterwards.

Where:
FuseIT Ltd,
Ground Floor,
7 Forests Rd,
Stoke,
Nelson
(Off Nayland Rd and behind Carters)

http://local.live.com/default.aspx?v=2&cp=-41.299774~173.236231&style=r&lvl=16&alt=-1000
or
http://maps.google.com/?ie=UTF8&om=1&z=17&ll=-41.299774,173.236231&spn=0.005239,0.010042&t=h

If you are parking on site, please use the parks marked FuseIT that are at the back of the site.

Giveaways:
A Microsoft Wireless Laser Mouse 5000

Catering: Pizza & Drinks
Door Charge: Free

RSVP to me if you are going to attend so I can guesstimate the food and drink requirements.

However, feel free to turn up on the day though if you can't commit at the moment.

Please feel free to invite anyone who may be interested in attending.

New Zealand Community SharePoint Conference

Planning has started for the New Zealand Community SharePoint Conference on 2/3 July 2009 (tentative dates) in Wellington.

You can register your interest in attending, speaking or sponsoring here: http://www.sharepointusergroup.net.nz/SPCONF/default.aspx

Seperating the ObjectDataSource Service and business objects

In hindsight this seems like a rather trivial example. Still, up until now I've always been configuring ObjectDataSource against a single class. This class provided the CRUD methods and the properties for whatever the data source was connected to.

An alternative approach is to separate the CRUD methods from the business object into a service object. E.g. :

Business object:

using System;

public class Car
{
    private string _vin;

    public string Vin
    {
        get { return this._vin; }
    }

    public Car(string vin)
    {
        this._vin = vin;
    }
}

Service:

using System;
using System.Collections.Generic;

public class CarService
{
 public CarService()
 {
 }

    public List<Car> Select()
    {
        List<Car> cars = new List<Car>();
        cars.Add(new Car("vin1"));
        cars.Add(new Car("vin2"));
        return cars;
    }
}

Default.aspx

    <form id="form1" runat="server">
    <div>
    
    <asp:GridView ID="GridView1" runat="server" DataSourceID="Objectdatasource1">
    </asp:GridView>
    <asp:objectdatasource ID="Objectdatasource1" runat="server" SelectMethod="Select" TypeName="CarService"></asp:objectdatasource>
    
    </div>
    </form>

Help getting IE6 off the web

IE6 has been with us for some time now and for a good part of that time it's been a real pain to develop for. It was made in simpler (more naive?) times before good CSS support was a sensible requirement for a web browser.

The problem most web developers now face is how to encourage everyone to upgrade to a more standards compliant browser.

Vincent Hasselgård posted some code to encourage IE6 users to upgrade their browsers. See Give IE6 users the message to upgrade or change

Will putting this code on developer focused sites help? Probably not. I'd be surprised to find a developer using IE6 by choice. Still, any step I can take in removing IE6 from the web is a step in the right direction.

Can the first day of a century fall on a Sunday? Proof by brute force

After reading Straight Dope: Can the first day of a century fall on a Sunday? I threw this code together. Not that I didn't believe their maths/logic, but I thought this would be a really easy thing to brute force with a couple of minutes coding.

        static void Main(string[] args)
        {
            Dictionary<DayOfWeek, int> fallsOnDay = new Dictionary<DayOfWeek, int>();
            foreach (DayOfWeek dow in Enum.GetValues(typeof(DayOfWeek)))
            {
                fallsOnDay.Add(dow, 0);
            }

            for (int year = 100; year < 10000; year += 100)
            {
                DateTime toTest = new DateTime(year, 1, 1);
                fallsOnDay[toTest.DayOfWeek]++;
            }

            foreach (KeyValuePair<DayOfWeek, int> dowCount in fallsOnDay)
            {
                Console.WriteLine(dowCount.Key + " " + dowCount.Value);
            }
            Console.ReadLine();
        }

Output:

Sunday 0
Monday 25
Tuesday 0
Wednesday 25
Thursday 0
Friday 25
Saturday 24

You change line 11 to easily test any other day of the year. For example:

DateTime toTest = new DateTime(year-1, 12, 31); //line 11 changed to test DOW before change in century.

Output:

Sunday 25
Monday 0
Tuesday 25
Wednesday 0
Thursday 25
Friday 24
Saturday 0