TruncateLog Property (Backup)
后续版本的 Microsoft SQL Server 将删除该功能。请避免在新的开发工作中使用该功能，并着手修改当前还在使用该功能的应用程序。
The TruncateLog property controls log file processing for Backup and BulkCopy objects.
语法
object
.TruncateLog [= value]
Parts
- object
An expression that evaluates to an object in the Applies To list.
- value
A long integer that specifies a database log file operation as described in Settings.
Data Type
Long, enumerated
Modifiable
Read/write
Prototype (C/C++)
HRESULT GetTruncateLog(SQLDMO_BACKUP_LOG_TYPE* pRetVal)
HRESULT SetTruncateLog(SQLDMO_BACKUP_LOG_TYPE NewValue)
Settings
| Constant | Value | Description |
|---|---|---|
SQLDMOBackup_Log_NoLog |
2 |
Records referencing committed transactions are removed. The transaction log is not backed up. |
SQLDMOBackup_Log_NoOption |
4 |
SQLDMOBackup_Log_Truncate. |
SQLDMOBackup_Log_NoTruncate |
1 |
The transaction log is backed up. Records referencing committed transactions are not removed, providing a point-in-time image of the log. |
SQLDMOBackup_Log_Truncate |
0 |
The transaction log is backed up. Records referencing committed transactions are removed. |
SQLDMOBackup_Log_/Truncateonly |
3 |
SQLDMOBackup_Log_NoLog. |
备注
For Microsoft SQL Server, transaction log backup can perform two distinct database administration tasks:
- Log backup can be part of a backup strategy allowing incremental recovery to a failure point.
- Log backup can remove log records referencing committed transactions, freeing space in a log of fixed size or allowing an autoresizing log to shrink.
When using the Backup object to perform administrative maintenance of a database log, set the TruncateLog property to SQLDMOBackup_Log_Truncate or SQLDMOBackup_Log_NoLog.