Disconnected Dataset Vs Connected RecoredSet

[Guest]

I have done many projects in VB 6.0 mostly database related. But when i
transfer in .NET platform, i wonder about disconnected dataset. I know there
is many many advantages of Disconnected dataset. But what can i do when i
make a project which shows stock exchange share prices or other sort of
projects where intime information is required.
For example, i fill the dataset with about 200 rows and one row is changed
after 1 sec. and i implement a logic that update local dataset after every 3
sec. what happen there. Whole dataset will be updated after every 3 second
because of some few rows changed. what you say about performance.

Please tell me if there is any machanism like connected recordset. I have
very few users but data changes rapidly and users should be updated instantly.
Thanks in advance

 

[William \(Bill\) Vaughn]

As I have discussed before ADO.NET does not support a server-side
cursor--not even in the 2.0 version. That said, there is nothing stopping
you from creating an ANSI cursor with a Connected application. I wrote a
whitepaper on this some time ago--it can be found on my site. In any case
you'll either have to implement Notification Services or wait for the 2.0
SqlDependecy SqlNotify functionality that will fire an event if the data
changes. These approach won't tell you which row changed, just that data in
the selected rowset has changed. You'll still have to process a query that
retrieves the current data values. There are a number of strategies to do
this including use of triggers and other notification systems.

hth

--
____________________________________
William (Bill) Vaughn
Author, Mentor, Consultant
Microsoft MVP
www.betav.com/blog/billva
www.betav.com
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[grant]

You can of course continue to use ADODB in your .NET applications with
connected recordsets as you did in your VB6 applications (just add a
refererence to ADODB). The main drawback of this that you don't get
the data binding support or strong typing that ADO.NET provides.
Infralution has a commercial product (Virtual Data Objects) that
addresses this by providing a mechanism to databind ADODB recordsets to
..NET controls (and also add strong typing). If you are interested you
can download a fully functional evaluation version at:

www.infralution.com/virtualdata.html