I'm struggling a bit with some of the base concepts of U2 Toolkit (and I've been quite successful with the previous version!).

First, I had to add using U2.Data.Client.UO; in order to reference UniSession or UniFile. This may just be general ignorance, but doesn't 'using U2.Data.Client' imply that I also want the .UO stuff under it?!?

Second - what (conceptually) are the differences between connecting via U2Connection's Open(), or UniSession's OpenSession()? Do each of them provide a different context in which to work?

Finally - while the examples provided in the doc and in Rajan's various articles are helpful, I'd like something a little more practical: how about a simple "here's how you read and write specific records in a Unidata file"?

Thanks!

Please see answer for the first and second questions

Regarding Namespace

If you want to develop application using ADO.NET ( SQL Access, UCI SERVER), you need one namespace (U2.Data.Client )

If you want to develop application using UO.NET ( Native Access, UO SERVER), you need two namespaces (U2.Data.Client and U2.Data.Client.UO)

U2.Data.Client namespace generally have Microsoft ADO.NET Specification Classes.

U2.Data.Client.UO namespace generally have UniObjects Native Specification Classes. As you have used in the past UODOTNET.DLL, you can feel all the Classes are there.

Regarding U2Connection/UniSession

This is by Design.

U2Connection.Open() calls UniSession.Open() when you use Accessmode=’Native’ in Connection String. You can verify from the LOG/TRACE File. In this case, basically, U2Connection and U2Session are same. U2Connection Class just passes connection string to UniSession Class and then UniSession Class uses this connection string and calls Open(). This is an improvement from the old way where you have used Static Class UniObjects(…) and there was no concept of standard connection string. Basically we replace Static Class UniObjects(…) to U2Connection Class and provided connection string capabilities.

U2Connection.Open() calls UCINET.Open() when you use Accessmode=’SQL’ in Connection String. You can verify from the LOG/TRACE File.

Is this clear()?