Thursday, August 17, 2006
Greatest Software Ever?
Well, I read through the article and other than a few quibbles here and there I'd have to say that the author did a good job of assembling his list. He spends quite a bit of time talking about the IBM 360 project - and well he should. This was one of the first truly huge software projects and it set the bar for what is expected of an operating system. It also was the catalyst for causing one of the best ever books on software development to be written - The Mythical Man Month. Written by Fred Brooks, the manager in charge of the IBM 360 project, this book outlines many of the truisms about software development that we acknowledge even today - more than 40 years later. If you work in IT and you haven't read The Mythical Man Month you really should buy a copy and read it immediately. Anyway, this blog isn't about that book, so let's move on.
I won't spoil it here and publish the list of greatest software - you will have to click on the link for the article and read it yourself (the actual list doesn't start until page 3 of the article, but don't just click right over to that page, read the whole thing).
Suffice it to say, several IBM projects make the list (I'm kinda partial to what came in at #2 -- it would've been my #1 actually). And I think perhaps that VisiCalc belongs on the list instead of the spreadsheet software that is listed - I mean, Dan Bricklin invented the entire spreadsheet category of software when Software Arts published VisiCalc back in the late 1970s.
But the article is good anyway and I'm sure it is almost impossible to publish a list like this without causing disagreement - and perhaps that is its intent any way. So take a moment and click over to the article and give it a read. And feel free to share your thoughts on it here by posting a comment or two.
Thursday, August 10, 2006
SHARE Travelers Take Heed
Basically, in response to a recently thwarted terrorist plot in the UK, the threat level has been raised to High (or Orange) for all commercial aviation operating in or destined for the United States. That means the lines will be longer and the searches more thorough going through security at the airport.
Additionally, please read the TSA announcement and heed what it is saying. I am referring specifically to this: "Due to the nature of the threat revealed by this investigation, we are prohibiting any liquids, including beverages, hair gels, and lotions from being carried on the airplane." Please, for everyone's sake, leave your liquids at home:
- You can get a drink after you pass through security.
- Every hotel provides shampoo, conditioner, and lotion for free, so you don't need to bring them.
- If you absolutely have to have your favorite brand, or some gel or spray, pack it in your checked bags.
And I'll see you all in Baltimore.
Wednesday, August 09, 2006
Where exactly is a DB2 plan stored?
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
Tuesday, August 08, 2006
Mainframe Weekly: A new mainframe-focused blog
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.
Monday, August 07, 2006
Upcoming SHARE Conference
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!