User Guide

SAP AG November 2002
You can perform interactive log backups in operating mode [Page
145] ONLINE
or ADMIN.
You cannot perform any other backup while the interactive log backup is running.
See also:
Backup Strategy [Page
39]
Saving Log Backups [Page
43]
Saving Log Backups
For information on how to save log backups [Page 142], refer to the following documentation:
• Database Manager GUI: SAP DB 7.4, Section Backup Procedure [See SAP DB Library]
• Database Manager CLI: SAP DB 7.4, Section Backing Up and Recovering Database
Instances [See SAP DB Library]
• Database Management in CCMS: SAP DB OLTP → DBA Planning Calendar
External Backup Tool
Backups [Page 126] can also be carried out using external backup tools on external backup
media.
A detailed description of the use of external backup tools can be found in the following
documentation: External Backup Tools: SAP DB [See SAP DB Library]
.
See also:
External backup medium [Page
138]
Name of external backup medium [Page
145]
External backup ID [Page 137]
Log Concept
One of the main, internal functionalities of the SAP DB database system is the logging.
In normal database operation (operating state [Page
145] ONLINE), the modifying SQL
statements of every transaction must be logged, meaning that log entries [Page
44] (redo
[Page 44] and undo log entries [Page 44]) are written. These log entries are required so that
the database system can ensure transaction consistency and so that individual SQL
statements can be reversed if required. In addition, the undo log entries are needed to enable
consistent reading when no locks are set.
The task of online logging [Page
44] is to store the log entries so that they are constantly
available for normal database operation.
In the case of a restart or recovery [Page
49], the required log entries must be made available
and processed in the correct time-based sequence.
User Manual: SAP DB 43