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JetGetRecordPosition Function

Windows

Last modified: January 09, 2012

Applies to: Windows | Windows Server

The JetGetRecordPosition function returns the fractional position of the current record in the current index in the form of a JET_RECPOS structure. This structure describes fractional positions in terms of an approximate number of index entries before the current record and an approximate total number of entries in the index.

JET_ERR JET_API JetGetRecordPosition(
  __in          JET_SESID sesid,
  __in          JET_TABLEID tableid,
  __out         JET_RECPOS* precpos,
  __in          unsigned long cbRecpos
);

Parameters

sesid

The session to use for this call.

tableid

The cursor to use for this call.

precpos

The description of the fraction to use in getting the position of the current record in the current index.

cbRecpos

The size of memory allocated at precpos.

Return Value

This function returns the JET_ERR datatype with one of the following return codes. For more information about the possible ESE errors, see Extensible Storage Engine Errors and Error Handling Parameters.

Return code

Description

JET_errSuccess

The operation completed successfully.

JET_errNotInitialized

It is not possible to complete the operation because the instance that is associated with the session has not been initialized yet.

JET_errClientRequestToStopJetService

The operation cannot complete because all activity on the instance that is associated with the session has ceased as a result of a call to JetStopService.

JET_errInstanceUnavailable

This operation cannot complete because the instance, associated with the session, encountered a fatal error. It is required that access to all data be revoked in order to protect the integrity of that data.

Windows 2000:  This error will not be returned by the Windows 2000 operating system.

JET_errInvalidParameter

The size of the allocated memory at precpos is not a sufficient size.

JET_errNoCurrentRecord

The cursor is not currently on a record and cannot return a position.

JET_errRestoreInProgress

It is not possible to complete the operation because a restore operation is in progress on the instance that is associated with the session.

JET_errSessionSharingViolation

The same session cannot be used for more than one thread at the same time.

Windows 2000:  This error will not be returned by the Windows 2000 operating system.

JET_errTermInProgress

The operation cannot complete because the instance associated with the session is being shut down.

On success, the approximate number of index entries preceding the current record in the index are returned in precpos->centriesLT. 1 is returned in precpos->centriesInRange. The approximate number of entries in the index is returned in precpos->centriesTotal.

On failure, no changes are made to memory allocated at precpos.

Remarks

This operation returns varying data when updates occur continuously on the table. The changes in the values will not always match expectations based on knowledge of the updates, since the values are approximations based on physical properties of the index. Transactional isolation does not apply to positions from JetGetRecordPosition since the values depend on physical properties of the index that are not transaction isolated.

JET_RECPOS should not be used to describe a record within a table or to reposition a record close to an existing record. Instead, bookmarks for an existing record should be retrieved and then used to reposition the same record.

Requirements

Client

Requires Windows Vista, Windows XP, or Windows 2000 Professional.

Server

Requires Windows Server 2008, Windows Server 2003, or Windows 2000 Server.

Header

Declared in Esent.h.

Library

Use ESENT.lib.

DLL

Requires ESENT.dll.

See Also

Afficher:
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