ReadBackupHeader Method (Restore)
Cette fonctionnalité sera supprimée dans une prochaine version de Microsoft SQL Server. Évitez d'utiliser cette fonctionnalité dans de nouveaux travaux de développement, et prévoyez de modifier les applications qui utilisent actuellement cette fonctionnalité.
The ReadBackupHeader method returns a QueryResults object enumerating the contents of the media maintained by a backup device or operating system file.
Syntaxe
object
.ReadBackupHeader(
Server
)
as
QueryResults
Parts
- object
Expression that evaluates to an object in the Applies To list.
- Server
SQLServer object connected to an instance of Microsoft SQL Server on which the device or file is visible.
Prototype (C/C++)
HRESULT ReadBackupHeader(
LPSQLDMOSERVER ServerObject,
LPSQLDMOQUERYRESULTS* ppResults);
Returns
A QueryResults object containing one result set. For a description of the result set contents, see ReadBackupHeader Method (BackupDevice).
Notes
When using the ReadBackupHeader method, one of the Restore object device properties must indicate the device or file maintaining the backup media.
To use the ReadBackupHeader method
Create a SQLServer object.
Connect the SQLServer object to an instance of SQL Server on which the source backup device is visible.
Create a Restore object.
Set either the Devices, Files, Pipes, or Tapes property to indicate a device visible on an instance of SQL Server indicated in Step 2 and maintaining the backup media. Specify only a single device or file.
If desired, set the FileNumber property to indicate a specific backup set by ordinal location on the media. By default, the header of the first backup set on the media is enumerated.
Call the ReadBackupHeader method of the Restore object using the SQLServer object created in Step 1 as an argument.
SQL Server can share backup media with other operating system utilities that perform backup of other data, and the media in a device may contain headers created by other utilities.
When the media of a backup device is unused, such as when a disk device is empty, the ReadBackupHeader method succeeds, returning an empty QueryResults object.