Today’s entry in our series on the DB2 DISPLAY command is the fifth – and final – edition of the series. We’ll wrap up coverage by briefly discussing the remaining features of DISPLAY. And, just as a reminder:
- Part 1 of this series focused on using DISPLAY to monitor details about you database objects;
- Part 2 focused on using DISPLAY to monitor your DB2 buffer pools;
- Part 3 covered utility execution and log information;
- And Part 4 examined using the DISPLAY command to monitor DB2 stored procedures and user-defined functions.
Additional Information that DISPLAY Can Uncover
The DISPLAY command can be quite useful in distributed DB2 environments. You can use DISPLAY DDF to show DDF configuration and status information, as well as statistical details on distributed connections and threads. An example of the output from issuing DISPLAY DDF:
DSNL082I LOCATION LUNAME GENERICLU
DSNL083I STLEC1 -NONE.SYEC1DB2 -NONE
DSNL084I TCPPORT=446 SECPORT=0 RESPORT=5001 IPNAME=-NONE
DSNL086I SQL DOMAIN=-NONE
DSNL090I DT=A CONDBAT= 64 MDBAT= 64
DSNL092I ADBAT= 0 QUEDBAT= 0 INADBAT= 0 CONQUED= 0
DSNL093I DSCDBAT= 0 INACONN= 0
DSNL105I DSNLTDDF CURRENT DDF OPTIONS ARE:
DSNL106I PKGREL = COMMIT
DSNL099I DSNLTDDF DISPLAY DDF REPORT COMPLETE
Additionally, DISPLAY LOCATION can be used to show information about distributed threads.
Data Sharing Information
For data sharing, the DISPLAY GROUP command can be used to display information about the data sharing group (including the version of DB2 for each member); and DISPLAY GROUPBUFFERPOOL can be used to show information about the status of DB2 group buffer pools.
If you have started using PROFILEs in DB2 10 (or later), the DISPLAY PROFILE command allows you to determine if profiling is active or inactive. The status codes that can be returned by this command are as follows:
- ON Profiling is active.
- OFF Profiling is inactive.
- SUSPENDED Profiling was active, but is now suspended due to error conditions.
- STARTING Profiling is being started, but has not completed.
- STOPPING Profiling has been stopped, but has not completed.
Resource Limit Information
If you use the Resource Limit Facility, the DISPLAY RLIMIT command can be used to show the status of the RLF, including the ID of the active RLST (Resource Limit Specification Table).
To display information about a DB2 thread connection or all connections, use the DISPLAY THREAD command. A DB2 thread can be an allied thread, a database access thread, or a parallel task thread. Threads can be active, inactive, indoubt, or postponed.
There are a number of options for displaying thread information, and you can narrow or expand the type and amount of information you wish to retrieve based on:
- Active threads, inactive threads, indoubt threads, postponed threads, procedure threads, system threads, or the set of active, indoubt, postponed, and system threads (see the descriptions under the TYPE option for more information)
- Allied threads, including those threads that are associated with the address spaces whose connection names are specified
- Distributed threads, including those threads that are associated with a specific remote location
- Detailed information about connections with remote locations
- A specific logical unit of work ID (LUWID)
And finally, the DISPLAY TRACE command can be used to list your active trace types and classes along with the specified destinations for each.
The DB2 DISPLAY command is indeed a powerful, yet simple tool that can be used to gather a wide variety of details about your DB2 subsystems and databases. Every DBA should know how to use DISPLAY and its many options to simplify their day-to-day duties and job tasks.