JET_DBINFOMISC Structure

Artikkel
08/26/2021

Applies to: Windows | Windows Server

JET_DBINFOMISC Structure

The JET_DBINFOMISC structure holds miscellaneous information about a database. This is the information that is contained in the database header.

    typedef struct {
      unsigned long ulVersion;
      unsigned long ulUpdate;
      JET_SIGNATURE signDb;
      unsigned long dbstate;
      JET_LGPOS lgposConsistent;
      JET_LOGTIME logtimeConsistent;
      JET_LOGTIME logtimeAttach;
      JET_LGPOS lgposAttach;
      JET_LOGTIME logtimeDetach;
      JET_LGPOS lgposDetach;
      JET_SIGNATURE signLog;
      JET_BKINFO bkinfoFullPrev;
      JET_BKINFO bkinfoIncPrev;
      JET_BKINFO bkinfoFullCur;
      unsigned long fShadowingDisabled;
      unsigned long fUpgradeDb;
      unsigned long dwMajorVersion;
      unsigned long dwMinorVersion;
      unsigned long dwBuildNumber;
      long lSPNumber;
      unsigned long cbPageSize;
    } JET_DBINFOMISC;

Members

ulVersion

The native version of the database engine that created the database. See JetGetVersion to retrieve the native version for the current database engine.

ulUpdate

Tracks incremental database format updates that are backward compatible.

ulVersion, ulUpdate =	Meaning
0x620,0	Original operating system Beta format (4/22/97).
0x620,1	Add columns in the catalog for conditional indexing and OLD (5/29/97).
0x620,2	Add the fLocalizedText flag in IDB (6/5/97).
0x620,3	Add SPLIT_BUFFER to space tree root pages (10/30/97).
0x620,2	Revert revision in order for ESE97 to remain forward-compatible (1/28/98).
0x620,3	Add new tagged columns to catalog ("CallbackData" and "CallbackDependencies").
0x620,4	SLV support: signSLV, fSLVExists in db header (5/5/98).
0x620,5	New SLV space tree (5/29/98).
0x620,6	SLV space map (10/12/98).
0x620,7	4-byte IDXSEG (12/10/98).
0x620,8	New template column format (1/25/99).
0x620,9	Sorted template columns (6/24/99).
0x623,0	New Space Manager (5/15/99).

signDb

Signature of the database (including creation time). This structure is 28 bytes.

dbstate

This is the database state.

The following options are available for this member.

Value	Meaning
JET_dbstateJustCreated 1	The database was just created.
JET_dbstateDirtyShutdown 2	The database requires hard or soft recovery to be run in order to become usable or moveable. One should not try to move databases in this state.
JET_dbstateCleanShutdown 3	The database is in a clean state. The database can be attached without any log files.
JET_dbstateBeingConverted 4	The database is being upgraded.
JET_dbstateForceDetach 5	Internal.

lgposConsistent

Null if the database is in a dirty state. This is the log position that was used when the database was last brought to a clean shutdown state.

logtimeConsistent

Null if the database is in a dirty state. This is the time when the database was last brought to a clean shutdown state.

logtimeAttach

The time when the database was last attached with JetAttachDatabase.

lgposAttach

The log position that was used the last time the database was attached with JetAttachDatabase.

logtimeDetach

The time when the database was last detached with JetDetachDatabase.

lgposDetach

The log position that was used the last time the database was detached with JetDetachDatabase.

signLog