Logical log output files
When you select records from the Db2 log,
Log Master
creates an intermediate file that contains all of the log records that meet the filter criteria. This intermediate file is a unique form of output called a logical log file.
Several files make up a logical log, including the logical log data file and the logical log control file. Both files must be variable blocked (VB) files. You can also generate an optional XMLSTRING control file if your logical log includes data from XML columns.
A logical log file can contain input from the following sources:
- The Db2 log
- A specific set of Db2 log files
- A previously created logical log file or set of previously created files
You can save the logical log as an output file of a log scan. You can then use logical logs as input for audit or data migration tasks. To enable subsequent ad hoc use of Log Master, you might choose to create logical logs and save them. You can then use the logical logs for input, and save the time required to scan the Db2 log.
Logical logs also provide a way to create audit files of data. By creating logical log files, you can save data for months, or years. You can still access and report on the data, even if the application has changed and the original logs have been deleted from your Db2 subsystem. Log Master can include DDL objects in your logical log files that can be interpreted as input by either Log Master or the High-speed Apply Engine.
You can use logical logs as input for other programs in your environment, or in subsequent runs of Log Master. BMC publishes the format of logical log files. The formats of the logical log control file and data file do not define an order for the records that they contain. The order of columns within the logical log data file is based on logical position within the base table, regardless of physical position within the table row. The column order is based on the COLNO column in the SYSIBM.SYSCOLUMNS table of the Db2 catalog.
The following example illustrates the use of logical logs. For this example, assume that you are occasionally required to produce audits for a payroll application. Instead of having to repeatedly re-create a search to select the same records from the Db2 log, you can generate a logical log output file. The logical log output file contains all of the information that you need to generate a report for that particular month’s payroll. The content of the file exactly represents the information logged by Db2 at the time that you ran payroll.
The following figure shows the Logical Log Output panel. Define an output logical log file by specifying values on this panel. For descriptions of the options on this panel, press F1 to access the online Help.
Command ===> __________________________________________________________________
SSID: DBAN
Logical Log . . . . . . . . . . . . _ (E=Edit)
FILE: &SYSUID..D&DATE..T&TIME..LLOG.DATA
Logical Log Control . . . . . . . . _ (E=Edit)
FILE: &SYSUID..D&DATE..T&TIME..LLOG.CNTL
Logical Log XMLSTRING Control . . . _ (E=Edit)
Date Format . . . . . . . . . . D (D=DB2I, S=SASTIME)
Expand VARCHAR columns . . . . . . . N (Y=Yes, N=No)
Create Include/Exclude Columns . . . _ (E=Edit)
Include Rollback . . . . . . . . . . N (Y=Yes, O=Only, N=No)
Include Command Records . . . . . . N (Y=Yes, O=Only, N=No)
Include DDL Objects . . . . . . . . N (Y=Yes, N=No)
Include LOBS . . . . . . . . . . . . N (Y=Yes, N=No)
Include XML . . . . . . . . . . . . N (Y=Yes, N=No)
Include SYNONYMS . . . . . . . . . . N (Y=Yes, N=No)
Include STATUS CHANGES . . . . . . . N (Y=Yes, O=Only, N=No)
For more information about the topics in this section, see the following references:
Topic | Reference |
|---|---|
Overview of how to use the interface to define and generate a logical log output file | |
Logical log files, including sorting |