![]() ![]() TRecordset2Read = dbOpenForwardOnly 'Does not affect TRecordsetExist = dbOpenDynaset 'Dummy recordset type: ' )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON īUseTrans = True 'Without transaction everything works well Doesn't affectĭim bTranInitiated As Boolean 'Track if we are in transaction If i use dbOpenDynaset in (1), i'll not see new record in (3).ĭim bUseTrans As Boolean 'New record added in transactionĭim rsExist As DAO.Recordset2 'Dummy recordsetĭim tRecordsetExist As DAO.RecordsetTypeEnum 'Dummy recordset type:ĭim rs2Read As DAO.Recordset 'Used to read recently added recordĭim tRecordset2Read As DAO.RecordsetTypeEnum 'Recordset type used to read new record. Is there any solution other than rewrite code using ADO?Ĭan i modify standard Access behaviour? ( use read uncommitted isolation level, instruct to not open new connections. I've tested this using ADO and everything works well. Transaction => Changes made in the first are not visible in the second. Access add/update and read records using a different connections independent server side Doesn't find new records and see existing records in the original state. If i add or update a record using recordsets, any code trying to read them will fail. Rules has been changed and code using client side transactions will fail. And every db change is visible by any code that runs in the same DAO.Workspace before executing commit. Standard behavior using linked tables to a. More than one connection means more than one transaction at time on server side. I've found a fustrating behavior: when i make changes using recordsets over linked tables, Access use more than one connection. We need a bit of more information here (the deadlock graph) to proceed ahead.I'm migrating a clasic Access application to Sql Server, i.e., DAO+Linked tables. The other thing that you might want to look into is what ISOLATION LEVEL you are using and also you might want to check is what are the kind of locks are on the temporary table and the USERS table at that point. INSERT INTO #PageIndexForUsers ( UserId ) I tried the following query batch below and this worked fine: The application with the transaction that terminated with an error can retry the transaction, which usually completes after the other deadlocked transaction has finished.ĭeadlocks generally happen if we have concurrent waits on the same resource trying to acquire incompatible locks on resources acquired by the SPIDs which are deadlocked against each other. This allows the other task to complete its transaction. ![]() If the monitor detects a cyclic dependency, it chooses one of the tasks as a victim and terminates its transaction with an error. ![]() The Microsoft SQL Server Database Engine deadlock monitor periodically checks for tasks that are in a deadlock. This condition is also called a cyclic dependency: Transaction A has a dependency on transaction B, and transaction B closes the circle by having a dependency on transaction A.īoth transactions in a deadlock will wait forever unless the deadlock is broken by an external process. Transaction A cannot complete until transaction B completes, but transaction B is blocked by transaction A. Transaction B now requests an exclusive lock on row 1, and is blocked until transaction A finishes and releases the share lock it has on row 1.Transaction A now requests an exclusive lock on row 2, and is blocked until transaction B finishes and releases the share lock it has on row 2.Transaction B acquires a share lock on row 2.Transaction A acquires a share lock on row 1.This is the definition of a deadlock from SQL Server Books Online:Ī deadlock occurs when two or more tasks permanently block each other by each task having a lock on a resource which the other tasks are trying to lock. ![]()
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