I hope this article, posted today on the DAW Development Team blog, clears up most questions.

It’s nice to live in a place with a thriving developer community and other coders who view software development as craftsmanship.

I also learned what a fishbowl is. Very cool!

My favorites are new features to make code navigation simpler:

• Call Hierarchy: being able to see in design mode what method calls and is called by other methods is brilliant! This is only available for C# in this revision, but that’s really the only .Net language I code in anyway.
• Navigate To: an easy way to type any part of an identifier name and find it anywhere in the current solution.

I’m really happy about this. One of the most cumbersome things when working in Visual Studio has been navigating through code.

I still miss one of the best features of Visual DataFlex Studio, Code Explorer, in Visual Studio. While I appreciate the improvements for making code easier to find in VS 2010, I always have Code Explorer open in the Visual DataFlex Studio. Code Explorer is a docking panel that displays the structure of the current code file. This makes it very easy to locate a class, object or method with a click.

Class View at first appears somewhat similar, but the way it’s implemented, it still takes a lot more steps to find something.

The database is SQL Server 2008 Express running on a Windows XP Pro SP3 PC. The database can still be accessed from the server PC itself and another Windows XP Pro PC. Attempting to connect from 2 Vista workstations, both Ultimate, but one 32 bit and the other 64 bit, now results in an error:

Connection failed:
SQLState: '01000'
SQL Server Error: 53
[Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Connect()).
Connection failed:
SQLState: '08001'
SQL Server Error: 17
[Microsoft][ODBC SQL Server Driver][DBNETLIB]
    SQL Server does not exist or access denied.

The same thing happens whether we use a trusted connection or the sa login (just for testing to check if the problem was a permissions issue).

I intended to post the solution to this issue here this week, but I haven’t found one yet. My hope was that if this was a result of a Windows update, I would find more information about it this first week of January as more people returned to work and others ran into the same issue.

Update:

I found the solution to this by simply debugging the problem based on the symptoms. All information I found about this error talked about opening ports to allow SQL Server access. The culprit was the Windows Firewall on the Windows XP Pro PC hosting the SQL Server database. One of my test steps was to temporarily disable the Windows firewall and this made everything work as before.

So, I enabled the firewall again and added exceptions for TCP port 1433 and UDP port 1434. This resulted in a different error (HYT00 “timeout expired”) during he initial login attempt, but worked on subsequent tries.  I was able to resolve this error by allowing outgoing time exceeded messages via ICMP in the Windows firewall settings.

None of these exceptions or allowances were ever enabled before this problem started, so something changed to cause this to happen. My money is still on some Windows or SQL Server security update. I wish I had more time to track this down further and find the culprit, but I’m happy to have a working solution now.

This is great; it allows you to develop and run a database application without requiring a connection to an SQL Server or even installing SQL Server on the client PC that runs the application. You can then use this as a standalone single user application or synchronize data between the application’s local cache and a running SQL Server database.

When you create a new strongly typed DataSet in the Studio via Data > Add New Data Source, if the data source is an SQL Server database, you get the option to “Enable local database caching”. If checked, Visual Studio will automatically create a Local Database Cache (.sync) file and add it to your project. The code in your DataSet is created using System.Data.SqlServerCe.SqlCexx so that your code can connect to the SQLCE database. It also creates the local SQLCE database (a .sdf file), and adds it to your project.

The key piece in this process is the Local Database Cache (.sync) file. This is what allows you to configure which tables can be cached in your local SQLCE database. If you bring up the Configure DataSet Wizard to either create or edit a DataSet and it won’t allow you to select some tables to be cached locally, you can create or edit the .sync file. The How to: Configure Data Synchronization to Use SQL Server Change Tracking page shows you how to create this file from scratch.

If you already have a .sync file, you can configure it by right-clicking on the file in Solution Explorer and choosing View Designer from the context menu. It’s kind of hidden, but if you click the Add button to add a table (provided there are more tables available in your database that can be added), you will see a link to Learn more about which tables can be cached…, which explains the rules determining which tables can be cached.

Look for future Visual DataFlex-related posts by myself and other members of the development team here.

Quite recently (August 2009) Amazon once again changed the name of their web services API and also the rules for making call to it, now requiring cryptographic signature authentication. While Amazon provides code samples, for some odd reason the only (yet new) C# SOAP sample provided by Amazon uses the dated and likely soon obsolete Web Services Enhancements (WSE) class library instead of Windows Communication Foundation (WCF). I assume this sample is for developers still using .Net 2.0, but a sample using more current technology would have been appropriate, as well.

I searched the web for a suitable sample to implement the signature authentication using .Net 3.5 and eventually came across a very appropriately titled blog entry: Signing Amazon Product Advertising API requests — the missing C# WCF sample, by Oren Trutner. Attached to Oren’s very appropriately titled blog entry are 3 samples that make implementing the calls using WCF very straightforward.

Great work and thanks, Oren!