Where exactly is a DB2 plan stored?

The title of this posting is a question I received awhile ago. As I promised earlier on this blog, I will periodically post the answers I have given to e-mailed questions. So, here goes:

A DB2 "plan" is stored in the DB2 Directory and information about the plan is stored in the DB2 Catalog.

The DB2 Directory table that contains actual plans is SYSIBM.SCT02 (and SYSIBM.SPT01 contains actual packages). The plan is stored as an internal structure called a cursor table; packages are stored as package tables. As DB2 runs application programs, it loads the cursor tables for plans and package tables for packages from the DB2 Directory tables into the EDM Pool. This is where the "access path" code that determines how to get the actual DB2 data resides.

There is also metadata about plans and packages that you might find useful. This information includes data about the state, privileges, isolation level, release specification, and so. The DB2 Catalog contains information about plans in the following tables:

• SYSIBM.SYSDBRM
• SYSIBM.SYSPLAN
• SYSIBM.SYSPLANAUTH
• SYSIBM.SYSPLANDEP
• SYSIBM.SYSSTMT
  

And, the DB2 Catalog contains information about packages in the following tables:

• SYSIBM.SYSPACKAGE
• SYSIBM.SYSPACKAUTH
• SYSIBM.SYSPACKDEP
• SYSIBM.SYSPACKLIST
• SYSIBM.SYSPACKSTMT
• SYSIBM.SYSPKSYSTEM
• SYSIBM.SYSPLSYSTEM

Mainframe Weekly: A new mainframe-focused blog

Mainframe Weekly is a new blog featuring the insights of Trevor Eddolls. Trevor is an editor who has worked for Xephon for some time. Xephon publishes those "Update" journals - you know the ones, DB2 Update, CICS Update, etc. The ones that are full of content and don't accept any ads.

I've had the pleasure of writing for DB2 Update and working with Trevor for a number of years now, and I look forward to regularly reading his new blog. Recent entries there have covered CICS, DB2 and Viper, and storage technology.

Do yourself a favor and be sure to check in on Trevor's blog on a regular basis.

Upcoming SHARE Conference

Just a quick posting to remind everyone that the bi-annual SHARE conference is coming up next week in Baltimore, MD. For those of you who don't know about SHARE: the conference has offered education to IT professionals, improving the value of IT to businesses, and advancing careers since 1955 - the longest history of any IT user group.

SHARE in Baltimore runs from August 13-18, 2006 and, as usual, there will be a plethora of useful and educational sessions on multiple IT topics. According to the folks at SHARE there will be over 800 technical sessions to choose from. Session topics range from implementation of new software releases to in-depth looks at what the latest new technologies can do for your business.

I'll be there, and will be delivering two presentations on DB2. On Monday, August 14, (3:00 - 4:00 PM) I'll give an hour of DB2 for z/OS tips and techniques... and then on Tuesday, August 15, (8:00 - 9:00 AM) I'll be giving an overview of DB2 for z/OS performance tuning.

Hope to see you there!

New Mainframe Redbook

IBM published a new mainframe redbook this week that everyone who works with mainframe technology should download and have handy. It is titled Introduction to the New Mainframe: z/OS Basics and it offers a very nice high-level overview of mainframe technology circa 2006.

Of course, if you are a long-time mainframer much of this redbook may be too high level for you. But it will be just the right thing to have at your disposal when someone drops by to ask a basic question. Just e-mail them a copy of the book.

And even long-time experts still might want to at least leaf through it. It is divided into four broad sections, as follows:

• Part 1. Introduction to z/OS and the mainframe
• Part 2. Application programming on z/OS
• Part 3. Online workloads for z/OS
• Part 4. System programming on z/OS

So maybe you are a crackerjack programmer, but would like to know more about system programming. Maybe your online knowledge is skimpy. Or maybe you just want a nice overview of everything. Then this book is just the ticket!

Here is a brief synopsis out of the Preface of the redbook:

This IBM Redbook provides students of information systems technology with the background knowledge and skills necessary to begin using the basic facilities of a mainframe computer. It is the first in a planned series of textbooks designed to introduce students to mainframe concepts and help prepare them for a career in large systems computing.

This textbook can also be used as a prerequisite for courses in advanced topics or for internships and special studies. It is not intended to be a complete text covering all aspects of mainframe operation, nor is it a reference book that discusses every feature and option of the mainframe facilities.

Others who will benefit from this course include experienced data processing professionals who have worked with non-mainframe platforms, or who are familiar with some aspects of the mainframe but want to become knowledgeable with other facilities and benefits of the mainframe environment.

So download Introduction to the New Mainframe: z/OS Basics today...

Network World: Mainframes Still Relevant

Just finished reading a great new article at NetworkWorld.com called Working on mainframes not just for old fogies. Well, that is sure good to know. I may be getting older, but I sure don't think of myself as one of those "old fogies" yet... and I still work on mainframes.

The article talks about the continuing relevance of mainframe computing in a novel way -- by talking to several young mainframe newbies. Yes, there are twenty-somethings out there who are working on mainframes, they are just hard to find. And the article makes the point that all of us in the mainframe world know -- we need more young 'uns to learn the mainframe.

The article goes on to point out some interesting mainframe statistics from the industry analysts. According to Gartner "large mainframe users have been increasing their mainframe environments for years." They say that installed MIPs will continue to gorw at a CAGR of 15 to 20 percent through 2009. And the analysts at IDC seem to agree, with 2006 MIPS shipments up 14.2 percent.

If you work on mainframes be sure to click over and give the article a read. To me, anyway, it is invigorating to hear about young people embracing the mainframe. And the more younger people who learn about mainframe computing, the stronger the platform becomes... and that is good, too.