How can I retain updates made in multiple locked rows and override scope rollback defined for row locking purposes ?

Question

I have a set of stored procedures in SQL
One of which is called to build a list of entries to submit to a web service
Those queries are called by identical processes running on different machines, so to prevent duplicate processing we lock rows that are presently being processed.
BEGIN
TRAN TRAN1
SELECT t.[TransactionId],t.[ContentIdentifier]
FROM [dbo].[Transactions]
t WITH(READPAST,
UPDLOCK,
ROWLOCK)where
(t.Quarantined
<> 1)
COMMIT
A Second stored procedure simply updates the Quarantined flag.
My C# code
TransactionOptions transactionOptions
=
new
TransactionOptions();
transactionOptions.IsolationLevel
=
IsolationLevel.ReadCommitted;
transactionOptions.Timeout
=
new
TimeSpan(0,
10,
0);
using (TransactionScope
scopeMain =
new
TransactionScope(TransactionScopeOption.Required,
transactionOptions))
TransactionsReady = DAL.GetFilesForProcessingByServiceType(i);
using (TransactionScope
scopeSuppress =
new
TransactionScope(TransactionScopeOption.Suppress,
transactionOptions))
foreach (var
Transaction in TransactionsReady)
{ try
returnData = proxy.Submit(stuffToProcess);
using (var
scopeInner =
new System.Transactions.TransactionScope())
DAL.QuarantineTransaction(Transaction.TransactionId);
scopeInner.Complete();
scopeSuppress.Complete();
scopeMain.Complete();
The problem I experience is that if I have the Transaction Scope scopeSuppress uncommented, then the QuarantineTransaction stored procedure deadlocks.
However if I comment out the ScopeSuppress, while the process then works, if it is interrupted mid-way, then all of the Quarantine flags get reset, meaning the entire batch of items will get re-submitted next
pass (this is not desirable).
What I actually want to occur, is for the Quarantine flag to be retained on all processed records so that even if the program terminates unexpectedly, processed items remain processed but all the row locks are
released.
Does anyone know of a way to achieve this ?

Answer 1

The hour is late where I sit, so I don't have the time to dive into this in detail.
However, if memory serves, TransactionScopes defaults to Serializable isolation level, which may explain the deadlocks you are getting.
Erland Sommarskog, SQL Server MVP, [email protected]