MDAC 2.5 SDK - OLE DB Programmer's Reference
Appendix C: OLE DB Properties

DBPROP_SUPPORTEDTXNISORETAIN

Property group: Data Source Information

Property set: DBPROPSET_DATASOURCEINFO

Type: VT_I4

Typical R/W: R

Description: Isolation Retention

A bitmask specifying the supported transaction isolation retention levels. A combination of zero or more of the following:

• DBPROPVAL_TR_COMMIT_DC—The transaction may either preserve or dispose of isolation context across a retaining commit.
  
  
• DBPROPVAL_TR_COMMIT—The transaction preserves its isolation context (that is, it preserves its locks, if that is how isolation is implemented) across a retaining commit.
  
  
• DBPROPVAL_TR_COMMIT_NO—The transaction is explicitly not to preserve isolation across a retaining commit.
  
  
• DBPROPVAL_TR_ABORT_DC—The transaction may either preserve or dispose of isolation context across a retaining abort.
  
  
• DBPROPVAL_TR_ABORT—The transaction preserves its isolation context across a retaining abort.
  
  
• DBPROPVAL_TR_ABORT_NO—The transaction is explicitly not to preserve isolation across a retaining abort.
  
  
• DBPROPVAL_TR_DONTCARE—The transaction may preserve or dispose of isolation context across a retaining commit or abort. This is the default.
  
  
• DBPROPVAL_TR_BOTH—Isolation is preserved across both a retaining commit and a retaining abort.
  
  
• DBPROPVAL_TR_NONE—Isolation is explicitly not to be retained across either a retaining commit or a retaining abort.
  
  
• DBPROPVAL_TR_OPTIMISTIC—Optimistic concurrency control is to be used. If DBPROPVAL_TR_OPTIMISTIC is specified, and then whatever isolation technology is in place (such as locking), it must be the case that other transactions' ability to make changes to the data and resources manipulated by this transaction is not in any way affected by the data read or updated by this transaction. That is, optimistic control is to be used for all data in the transaction.

For more information, see ITransactionLocal::StartTransaction.