The ReadBackupHeader method returns a QueryResults object enumerating the contents of the media maintained by a backup device.
object.ReadBackupHeader( ) as QueryResults
| Part | Description |
|---|---|
| object | Expression that evaluates to an object in the Applies To list |
A QueryResults object containing one result set defined by these columns.
| Column | Data type | Description |
|---|---|---|
| BackupName | nvarchar(130) | Backup set name. |
| BackupDescription | nvarchar(256) | Backup set description. |
| BackupType | tinyint | Backup type: 1 = Database 2 = Transaction Log 4 = File 5 = Differential Database |
| ExpirationDate | smalldatetime | Expiration date for the backup set. |
| Compressed | tinyint | 0 = False. Microsoft® SQL Server™ does not support software compression. |
| Position | smallint | Position of the backup set in the volume. |
| DeviceType | tinyint | Number corresponding to the device used for the backup operation: 2 = Temporary disk device 102 = Permanent disk device 5 = Temporary tape device 105 = Permanent tape device 6 = Temporary named pipe device 106 = Permanent named pipe device 7 = Temporary virtual device 107 = Permanent virtual device Device names for permanent devices can be found in sysdevices. |
| UserName | nvarchar(130) | Name of user that performed the backup operation. |
| ServerName | nvarchar(130) | Name of the server that wrote the backup set. |
| DatabaseName | nvarchar(130) | Name of the database that was backed up. |
| DatabaseVersion | integer | Version of the database from which the backup was created. |
| DatabaseCreationDate | smalldatetime | Date and time the database was created. |
| BackupSize | numeric(20,0) | Size of the backup, in bytes. |
| FirstLsn | numeric(25,0) | Log sequence number of the first transaction in the backup set. NULL for file backups. |
| LastLsn | numeric(25,0) | Log sequence number of the last transaction in the backup set. NULL for file backups. |
| CheckpointLsn | numeric(25,0) | Log sequence number of the most recent checkpoint at the time the backup was created. |
| DatabaseBackupLsn | numeric(25,0) | Log sequence number of the most recent full database backup. |
| BackupStartDate | smalldatetime | Date and time that the backup operation began. |
| BackupFinishDate | smalldatetime | Date and time that the backup operation finished. |
| SortOrder | smallint | Server sort order. This column is valid for database backups only. |
| CodePage | smallint | Server code page or character set used by the server. |
| CompatibilityLevel | tinyint | Compatibility level setting of the database from which the backup was created. |
| SoftwareVendorId | integer | Software vendor identification number. For SQL Server, this number is 4608 (or hexadecimal 0x1200). |
| SoftwareVersionMajor | integer | Major version number of the server that created the backup set. |
| SoftwareVersionMinor | integer | Minor version number of the server that created the backup set. |
| SoftwareVersionBuild | integer | Build number of the server that created the backup set. |
| MachineName | nvarchar(130) | Name of the computer that performed the backup operation. |
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.
HRESULT ReadBackupHeader(
LPSQLDMOQUERYRESULTS* ppResults);