Articles & Content

Robert Catterall

Robert Catterall is a well-known DB2 z/OS expert. He is a regular speaker at IDUG events and a Past President of IDUG

Note: The content of this blog is the opinion and thoughts of the blogger and does not necessarily represent the opinions of IDUG and should not be construed as reflecting official positions of the IBM Corporation. .

 

 
Db2 12 SQL Enhancement: Temporal Logical TransactionsTemporal data support, introduced with Db2 10 for z/OS, is one of the more interesting SQL-related Db2 enhancements delivered in recent releases of the DBMS. Temporal data support comes in two flavors (which can both be utilized for a single table): business-time temporal and system-time temporal. W…
Db2 12 for z/OS: Enhanced Lock Avoidance in Data Sharing EnvironmentsIn the last entry posted to this blog, I described the mechanisms (including PUNC bits and commit log sequence numbers, aka CLSNs) used by Db2 for z/OS for lock avoidance purposes (lock avoidance here refers to a capability whereby Db2 can, in many cases, verify the committed state of a data value w…
Db2 for z/OS: Lock AvoidanceNot long ago, I served as part of the teach team for a Db2 12 for z/OS Technology Workshop that IBM offered in a city in the USA. During that workshop, I covered, among other things, a Db2 12 enhancement that can improve the CPU efficiency of a Db2 data sharing system by reducing locking activity in…
Db2 12 for z/OS SQL Enhancements: Advanced TriggersIn this, the fourth of a set of four entries covering SQL enhancements introduced with Db2 12 for z/OS, I will describe new trigger capabilities delivered by way of what are called "advanced triggers" (the kind of trigger that you could define prior to Db2 12 -- and which you can still create in a D…
Db2 12 for z/OS SQL Enhancements: a Better MERGEGreetings, and welcome to the third in a series of entries covering my favorite Db2 12 for z/OS SQL enhancements. The first two posts in the series described piece-wise DELETE and result set pagination. This entry focuses on the new and very much improved MERGE functionality delivered via Db2 12 (us…
Db2 12 for z/OS SQL Enhancements: Result Set PaginationIn this second of a series of entries on my favorite SQL-related enhancements provided via Db2 12 for z/OS (and "Db2," versus "DB2," is officially the new form of the product name), I will describe useful functionality pertaining to result set pagination (my first post in this series covered piece-w…
DB2 12 for z/OS SQL Enhancements: Piece-Wise DELETEDB2 12 for z/OS, which became generally available in October of 2016, delivered a number of key enhancements pertaining to SQL statements. Over the course of a few blog entries, I'll describe some of my favorites among these enhancements. This first post in the series will cover piece-wise DELETE. …
DB2 for z/OS and Data-as-a-Service and Database-as-a-Service______-as-a-service is all the rage in IT these days, and understandably so -- the "service-ization" of information technology capabilities and interfaces will be transformational; indeed, transformations have already occurred or are underway at many organizations and within many application develop…
DB2 for z/OS: Something You Might Not Know About Large Page Frames in a Post-DB2 10 EnvironmentI well remember the first time I saw it. August, 2016. I was looking at output from the DB2 for z/OS command -DISPLAY BUFFERPOOL(ACTIVE) DETAIL, issued on a DB2 11 system, that a client had sent to me for review. I appreciated the fact that I could see in this command output information about DB2's …
DB2 for z/OS: Running REORG to Reclaim Disk SpaceThink of why you run the DB2 for z/OS REORG utility, and a number of reasons are likely to come quickly to mind: to restore row order per a table's clustering key; to reestablish free space (for inserts and/or for updates); to remove the AREO* status set for a table space following (for example) an …