ITransactionLocal::StartTransaction

OLE DB Programmer's Reference

Begins a new transaction.

HRESULT StartTransaction (    ISOLEVEL                isoLevel,    ULONG                   isoFlags,    ITransactionOptions    *pOtherOptions,    ULONG                  *pulTransactionLevel);

Parameters

isoLevel

[in]
The isolation level to be used with this transaction. For more information, see "Isolation Levels in OLE DB" in Chapter 15: Transactions.

Value	Description
ISOLATIONLEVEL_UNSPECIFIED	Applicable only to ITransactionJoin::JoinTransaction. Invalid for ITransactionLocal or for setting isolation level while in auto-commit mode.
ISOLATIONLEVEL_CHAOS	Cannot overwrite the dirty data of other transactions at higher isolation levels.
ISOLATIONLEVEL_READUNCOMMITTED	Read Uncommitted.
ISOLATIONLEVEL_BROWSE	Synonym for ISOLATIONLEVEL_READUNCOMMITTED.
ISOLATIONLEVEL_READCOMMITTED	Read Committed.
ISOLATIONLEVEL_CURSORSTABILITY	Synonym for ISOLATIONLEVEL_READCOMMITTED.
ISOLATIONLEVEL_REPEATABLEREAD	Repeatable Read.
ISOLATIONLEVEL_SERIALIZABLE	Serializable.
ISOLATIONLEVEL_ISOLATED	Synonym for ISOLATIONLEVEL_SERIALIZABLE.

isoFlags

[in]
Must be zero.

pOtherOptions

[in]
Optionally a null pointer. If this is not a null pointer, it is a pointer to an object previously returned from ITransactionLocal::GetOptionsObject called on this session instance.

pulTransactionLevel

[out]
A pointer to memory in which to return the level of the new transaction. The value of the top-level transaction is 1. If pulTransactionLevel is a null pointer, the level is not returned.

Return Code

S_OK: The method succeeded.
DB_E_OBJECTOPEN: A rowset object was open, and the provider does not support starting a new transaction with existing open rowset objects.
E_FAIL: A provider-specific error occurred.
E_UNEXPECTED: An unknown error occurred, and the method failed.
XACT_E_CONNECTION_DENIED: This session could not create a new transaction at the present time due to unspecified capacity issues.
XACT_E_CONNECTION_DOWN: This session is having communication difficulties with its internal implementation.
XACT_E_ISOLATIONLEVEL: Neither the requested isolation level nor a strengthening of it can be supported by this transaction implementation, or isoLevel was not valid.
XACT_E_LOGFULL: A transaction could not be created because this session specifies logging to a device that lacks available space.
XACT_E_NOISORETAIN: The requested semantics of retention of isolation across retaining commit and abort boundaries cannot be supported by this transaction implementation, or isoFlags was not equal to zero.
XACT_E_NOTIMEOUT: A noninfinite time-out value was requested, but time-outs are not supported by this transaction.
XACT_E_XTIONEXISTS: This session can handle only one extant transaction at a time, and there is presently such a transaction.
The session supports a limited number of nested transactions, and that limit has been reached.

Comments

ITransactionLocal::StartTransaction starts a new local transaction. If there is already an active transaction on the session (that is, StartTransaction has been called with no matching ITransaction::Commit or ITransaction::Abort), the new transaction is started as a nested transaction below the current transaction. Calling ITransaction::Commit or ITransaction::Abort always commits or aborts the transaction at the lowest level, respectively. If the provider does not support nested transactions, calling ITransactionLocal::StartTransaction when there is already an active transaction on the session returns XACT_E_XTIONEXISTS.

See Also