Transactions and Performance

In versions 1.x and 2.x of Microsoft Jet, it was generally recommended that you use transactions as a performance enhancement. In almost every case, wrapping DAO updates in a transaction is much faster in versions 1.x and 2.x because the transaction forces the engine to buffer changes in the cache rather than writing them directly to disk. However, various performance enhancements have been made in Microsoft Jet 3.0 and 3.5 to remove the need to use transactions for performance reasons.

See Also For more information about Microsoft Jet 3.5 performance enhancements, see Chapter 13, “Optimizing Performance.”

Microsoft Jet 3.0 and 3.5 provide automatic, internal transactions for all DAO add, update, and delete operations. In most situations, this automatic support provides your application with the best possible performance. However, there may be situations where you want to fine-tune the engine’s internal transaction behavior. You can do this by creating and modifying various settings in the Windows registry.

See Also For more information about the registry settings used by Microsoft Jet, see Chapter 13, “Optimizing Performance,” and Appendix D, “Registry Settings.”

The default settings used by Microsoft Jet for controlling transactions are generally the best available for general-purpose application design. However, you may find that tuning these settings yourself may enable the engine to better handle your data.