Delegates and the Database

So you know that cool problem I mentioned the other day.  Well before I present you with the complete solution I actually have to build up to it.  First off let me start off by saying that just like most Object oriented applications that use a database, ours has an ORM layer (ORM= Object to Relational Mapping).  Needless to say we rolled our own OR mapping, because at the time we felt we may not need a heavy weight one and didn’t have the time to analyze all the ORM frameworks out there.  Essentially we are using delegates to pass into our database execution engine.  The delegate uses IDataReader to read all the data out, because it’s a delegate the engine invokes the delegate AND gets to wrap it up in try catch logic to clean up should an exception occur.

http://www.pluralsight.com/blogs/keith/archive/2007/04/11/46711.aspx over at Pluralsight they call it enveloped abstractions.   Our code is similar to what they showing at this blog. 

This use of delegates is extremely cool, however it makes it a little difficult to support transactions and nested transactions (across multiple objects).  Also when you throw mirroring into the equation then dual rail support (2 connection strings) things start getting a little hairy.  So tomorrow I’ll be sharing some information about what I did to solve the problem

 

Veterans Day

I’ve never given a ton of thought to Veteran’s Day, other than to say thanks to all the veterans that have served our country.  But with Iraq so firmly entrenched in our lives I can’t help but think a lot MORE about the men and women who serve our country in the armed forces.  

I first off want to say a heartfelt thanks to them for risking their lives for the freedoms that we enjoy in our country.  If it was not for you (past and present) we would not be here today.

I also wonder if I should be apologizing for the way our leaders run this country.  It’s them who decide to put our military into action and then when it’s time to come home our leaders make it difficult for lots of veterans to reassimilate back into society.

Regardless, I hope that Iraq ends soon and you all can come home safe and hail. 

 

Autumn leaves are falling

all over my lawn.  It’s time to go make a GIGANTIC leaf pile and jump on it  

 

Happy Saturday

Today’s a busy day here at the home,  my oldest has gymnastics, a birthday party, I’m taking my youngest to see “curious george” over at the library.  And we are having a blind wine tasting at our house with my wine tasting group.  Usually we pick a type of wine to taste and pick up a few bottles.  Tonite we are doing something a little different.   I picked up a few bottles but each one is a different grape.  And as people taste they are going to try and figure out what type of grape the wine is made from.

And of course there’ll be the generall kibitzing and merriment that we usually have

 

Law of Demeter

So I’m still working on my Cool problem from yesterday, but in doing some research on it (and TDD) I stumbled across a “Law” of software programming that was kind of interesting.  

http://en.wikipedia.org/wiki/Law_of_Demeter

Check it out there.  Basically it says that Objects should assume as little as possible about structure and properties of anything else (including subcomponents).    It’s an interesting law which I think I use all the time when I am trying to “break” dependencies.  I usually TRY to create objects that explicitly state what they need (ctor params and method params).   

Another law that I’ve heard put into words recently is the Single responsibility principle.  Objects (and even methods) should have singular responsibilities.

I think I would call the Law of Demeter a corollary to SRP.  But I could also make an argument that the laws overlap.

I’ll have to think about this more

 

Parasitic twin

I’ve heard of sibling rivalry before … but for the first time ever today I heard the term parasitic twin.  I am constantly amazed at how bioligical systems “form” and adapt.  Apparently a girl in India was born with 4 arms and 4 legs, and 4 kidneys. While in the womb, the twin “died” and the girl’s body absorbed the bits and pieces of the twin… I’m assuming as a means of making sure she survived (otherwise I would assume both would have died).  

At first I thought the parasitic was applied to the twin that died but after thinking about it… I’m not so sure!

 

Daylight savings strikes back!

Well saturday and yesterday were good from the time shift.  But let me tell you … It really hit the girls hard today..  I got home from work and my oldest was asleep on the couch with a fever and come bed time my youngest was inconsolable.  It’s wierd how something like a time shift just throws the whole world out of balance for a few days. 

 yeesh!

 

Man vs. Domicile… Hooligan’s Home!

So I’m blatantly stealing a concept from James over at Aces Full of links (www.drmomentum.com/aces).  As a software engineer I gotta say that my “carpentry” skills are not so good, although I am very careful when I use power tools.  I just inherited a powertool from my grandpa who passed recently.  I was at his house today helping clean out and we came home with some interesting stuff.  I inherited a table saw!  And a skill saw, now along with my bench grinder I find I need to make a work space down in my spaceous cellar.   I hope to figure out how to use it (google here I come) and start planning how I can build a workbench.  Wish me luck!

I also got some 1944 pennies and a couple of coins that are pretty worn one is a quarter and one is a dime.  The date is worn off of the quarter but the dime’s date says 1886.  wow that’s old.  I hope to post some pics of them soon.

 

Wind, Rain, Floods … and Soccer!

Hello there!

This morning the remenants of Noel are hitting our area.  High winds, lot’s of rain, flooding, power outages are all predicted.  Yet since the rain hasn’t gotten here yet(but I see the wind picking up).  My daughter’s last soccer game is still on.  It’s fun to watch them play, and I’m not writing this post to complain.  I just find it funny that of all the outdoor sports, soccer seems to cancel the least

 Here’s hoping my raincoat keeps the water out!

 

Happy November!

Can you believe that November is here?  I can’t.  Another year is flying by.  Halloween was fun this year.  The girls are getting a little older (6 and almost 4) and they managed to walk the whole neighborhood this year getting their loot!

The one hitch was that we all met at a neighbor’s for some food but the food(pizza) didn’t arrive until after we had to hit the trail and get our treats.  However my neighboor put the pizza into a red wagon and came and found us, so we ate whist we walked.

Now that November is here I’m hoping my weekends get a little less hectic (September and October are extremely busy months for us).

I fixed up my last post on lightweight code generation.  (Thanks to Rjae over at www.thoughtshapes.com for showing me how to keep the formatting).   In the near future I’m hoping to talk about Unit Testing and some of what I’ve been doing at work.