understanding IsolationLevel

Hello,

Would someone out there point me to a place where I can get a good
understanding of when to use which IsolationLevel in
SqlConnection.BeginTransaction()? I read it from a couple of places but
none gave me some sort of guidelines when to use which. At this point, I do
my datalayer reading with RepeatableRead and saving with Serializable. So
far, occasionally I see some deadlock exception from sql server, not sure if
it's the cause; another concern is the performance cost of Serializable when
I don't have to.

Thanks!

Mahesh
Fri Dec 19 20:49:43 CST 2003

Hi,

The isolation level describes the degree to which the
data being updated is visible to other transactions.
You can keep ur Isolation either at ur COM+ level or at
ur ADO.NET or at the SQL Server level.It depends upon
what kind of operation you are performing in ur
application.

Since ur question is pertaining to ADO.NET Check this
very good article on Isolation level
http://www.visual-basic-data-
mining.net/Forum/ShowPost.aspx?PostID=930
http://www.devx.com/codemag/Article/17905/0/page/1

Check this powerpiont on Isolation Level
http://www.neodbug.org/ADO_NETBestPractices.ppt

If still you couldnt understand the concept behingd
Isolation Level, Please shoot a mail.

Regards
Mahesh ChandraMouli
Microsoft .NET MVP|MCAD


>-----Original Message-----
>Hello,
>
>Would someone out there point me to a place where I can
get a good
>understanding of when to use which IsolationLevel in
>SqlConnection.BeginTransaction()? I read it from a
couple of places but
>none gave me some sort of guidelines when to use which.
At this point, I do
>my datalayer reading with RepeatableRead and saving with
Serializable. So
>far, occasionally I see some deadlock exception from sql
server, not sure if
>it's the cause; another concern is the performance cost
of Serializable when
>I don't have to.
>
>Thanks!
>
>
>.
>