The following features are new for Windows Vista and Windows Server 2008:

• A new Unicode API has been added. All string parameters can be entered as an ASCII variant (JetCreateDatabaseA) and a new Unicode variant (JetCreateDatabaseW). This feature is enabled by the JET_UNICODE macro.

  The Unicode version of the API is available only on Windows Vista, and will not be available on earlier versions of the operating system. Applications developed on earlier versions of the operating system should continue to use the legacy version (JetCreateDatabase) of the API.

• Configuration settings change the default values of system parameters to optimize resource consumption of the database engine for applications. Setting the global configuration for JET_paramConfiguration to 0 enables this feature for all system parameters.
• Longer key lengths for searching and indexing are now available. Keys were limited to JET_cbKeyMost (255 bytes) in previous versions. In Windows Vista, and Windows Server 2008, the maximum key size is defined by the size of the byte-page and range from 500 (JET_cbKeyMost2KBytePage) to 2000 (JET_cbKeyMost8KBytePage) byte-pages long. To enable the maximum key size, set the Jet_bitIndexKeyMost option in the JET_INDEXCREATE structure.
• Callback notifications in the database are no longer enabled by default. Applications can enable persisted callback notifications by setting the JET_paramEnablePersistedCallbacks parameter.
• Index entries can be generated for all combinations of multi-valued key column values specified in the index. To enable the new indexing feature, set the JET_bitIndexCrossProduct option in the JET_INDEXCREATE structure.
• Reliability enhancements such as the single-bit error correction are available in the checksum of the database page.
• Second-generation log files are now available; the file extensions for transaction log files and the checkpoint files can be set to .jtx and .jcp, respectively, in order to avoid collisions with existing file associations. The range of log file names has been expanded to enable a larger number of log and resource files.
• New columns types include JET_coltypGUID, JET_coltypUnsignedLong, JET_coltypLongLong, and JET_coltypUnsignedShort.

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Build date: 9/6/2007