ADO.NET, LINQ, DataSet and other fun .NET technology

Download hotfixes

2008-07-04T00:51:00Z

Sometimes you run into a bug in DataSet, or some other product. At this point, you have a couple of choices. You can work around the bug, or you can call CSS/PSS. Most people take the former route unless they can't figure out a workaround. When you call PSS/CSS, you sometimes get a patch (hotfix), either one that exists, or a new one produced to fix the issue that you have. Wouldn't it be nice if you could cut out the middle step, and just download the patch? Now you can... See Soma's post for more...(read more)

Tech Ed

2008-05-30T19:28:00Z

I'm currently down in sunny Orlando, getting ready for Tech Ed (or is it TechEd? That dot between letters is a very odd thing). I'm going to be presenting on LINQ to DataSet, and Understanding the Entity Framework. As usual, I have far too much material for the time that I have. So I ask you, what aspects of LINQ to DataSet or the Entity Framework would you like me to focus on? Are there particular areas that are confusing, or that deserve attention? As well as the sessions, I will also be doing...(read more)

LINQ to DataSet - LinqDataView and indexes

2008-05-19T22:37:00Z

Index usage One of the features of the DataView that often gets overlooked is its ability to very quickly find a DataRow (or multiple DataRows) by an index value. The index is built on the sort criteria, so if you sort based on the last name column, the index will also be on the last name. In the 2.0 version of the DataSet, this was restricted to a column value. Now, with LinqDataView, this can be the result of a functional evaluation, that is, anything at all, which really opens up new possibilities....(read more)

DataSets and nullable types

2008-05-16T05:14:00Z

Let's say you want to have a DataSet with an Integer column, and this column can have no values, which for argument's sake we'll call NULL values (there is a whole argument about NULL really means, but we'll punt on that). The DataSet has been around since the first version of the .NET Framework, and this problem has always existed, as has it's solution, DBNull. This works ok, but leads to a bunch of ugly code like the following. int value = -1; // or some const value that represents null if (dataRow.IsNull(...(read more)

How'ya doing, where'ya been?

2008-05-16T03:29:00Z

It's been a while - but don't worry, I didn't drop off the face of the planet, or get eaten by huge worms. In the time since my last post, I've taken on some new responsibilities, namely a number of XML technologies, including those that are shipping in Silverlight 2! So look forward to new posts on this exciting new technology as well as on DataSet and the Entity Framework. Thanks, Erick...(read more)

EnumerableRowCollection Type

2007-11-07T04:40:00Z

If you've been playing with LINQ to DataSet, you may have noticed the EnumerableRowCollection type. For example, if you have a query like the following, the type of query is EnumerableRowCollection. var query = from row in ds.Tables[0].AsEnumerable() where row.Field< string >( "name" ) == "Bob" select row; So what is this type and what is it used for? As you know, the return type for any particular call must exist. While LINQ works with IEnumerable<T>, there still needs to be an implementation...(read more)

LINQ to DataSet Data Binding – LinqDataView Restriction Joins

2007-10-24T21:39:00Z

LINQ To DataSet Data Binding – LinqDataView restriction joins In previous episodes In the last post I made on LINQ To DataSet Binding, I talked about how to create a LinqDataView. I’m going to spend some time today talking about some of the interesting applications that the LinqDataView allows. This is far from a comprehensive list, and I’m sure that people will even more creative ways to use LinqDataView in the future! Our old friend, the AdventureWorks Schema All the examples that I’m working with...(read more)

LINQ to DataSet Data Binding – Introducing LinqDataView

2007-10-05T23:22:00Z

It's long overdue, but I finally was able to finish a few more posts on this series. Let me know if you find it helpful, and what you would like to see more of! Why DataView? As mentioned in this previous post , there are numerous options for data binding with LINQ to DataSet. The post is going to talk about what I feel is the most powerful and flexible option, LinqDataView. LinqDataView? While I will be talking about LinqDataView as a new object, it is in fact the same old DataView that we know...(read more)

Want to see my source?

2007-10-04T23:24:00Z

Have you ever wondered exactly what is going on inside of ADO.NET? Is Reflector the first thing you install after Visual Studio? Then you'll be interested in that fact that ScottGu just announced that the source for the .NET framework is going to be released. Not just released, but integreated with Visual Studio! Check out the announcement below. http://weblogs.asp.net/scottgu/archive/2007/10/03/releasing-the-source-code-for-the-net-framework-libraries.aspx I know I've been remiss in posting the...(read more)

PASS 2007 - Happening now in Denver

2007-09-18T23:36:00Z

I'm currently in Denver for the SQL Server PASS conference. I'll be giving a talk about the Entity Framework for DBAs tomorrow (Wednesday) afternoon. If you're there, please come by. Even if you can't make my session, stop by and say hello! Thanks, Erick...(read more)

LINQ to DataSet – Data Binding

2007-08-24T22:39:00Z

With the introduction of LINQ to DataSet there finally exists a full featured query language for the DataSet. Now your ability to query your data is limited only by CLR, which is no small thing! For an introduction on LINQ to DataSet, please see this post . This is great new functionality, but for most applications, query is only half of the story. Once you have sliced and diced your data into the form that you want, you need to do something with this data. This might be something as simple as spitting...(read more)

Entity Framework starting points

2007-08-01T02:44:00Z

I was recently asked what a high level list of good starting points for the Entity Framework is. This is a tough question as there are a lot of areas to cover. I've put together a list that I think makes sense from my perspective, which is tilted towards gaining an understanding of the model and the relational mapping, as opposed to getting up and running quickly. Most of the links refer to other blog posts, as these are the resources that I am familiar with. Understanding the model The core the...(read more)

Entity Framework for DBAs

2007-05-04T04:22:00Z

There are a host of new technologies coming out, and among them are some ORM type of systems. I want to spend some time exploring how a DBA will work with these, and if they are good or bad. Given that I am on the Entity Framework team, that is the place that I want to start. Entity Framework for DBAs There are two new data access technologies coming out of Microsoft in the coming year that have particular interest for DBAs: the Entity Framework and LINQ to SQL. Both of these technologies are going...(read more)

LINQ to DataSet WebCast (May 2, 2007) - Samples and slides

2007-05-02T21:50:00Z

This morning I performed a MSDN WebCast on LINQ to DataSet. I hope it was useful for people, and that I was able to answer all the questions sufficiently. If you missed the live show, you can always catch the "TiVo" version (i.e., on demand webcast). I'll update this post with the URL once it is posted. Here is the link to view the webcast . If you have any feedback, either on the content or presentation, please feel free to let me know. I promised that I would post the samples, and so here they...(read more)

Beta 1 Orcas Samples - LINQ to Entities

2007-05-02T06:31:00Z

With all the sample confusion during the March CTP, you will be pleased to know that the sample story for Beta 1 is much more smooth. You can find the complete working set of samples at the following URL.

http://msdn2.microsoft.com/en-us/bb330936.aspx

This sample set includes the full suite of LINQ samples, including LINQ to Entities.

As you may have heard, the Entity Framework will not be shipping alongside of Orcas. As such, when Beta 2 is released the LINQ to Entities samples will be found along with the rest of the Entity Framework, in a distinct CTP. Keep your ears open for announcements regarding this!

Erick