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 for z/OS Character Columns: Thoughts on CHAR versus VARCHARRecently, I received from a Db2 for z/OS DBA a question: for a table column that will hold character string values, are there any recommendations concerning the use of CHAR (fixed-length) versus VARCHAR (variable-length) for the column's data type? That question has been asked, I think, many times …
Db2 12 for z/OS RPN Table Spaces: New Possibilities for Range-Partitioned TablesSometimes, I assume that I've blogged about some Db2 for z/OS-related topic when in fact I have not. RPN table spaces is one such topic. In thinking about something to post this month, I briefly considered RPN table spaces and thought, "Nah. I've probably already blogged on that subject, given that …
A Case Study - Db2 for z/OS High-Performance DBATsOver the years, I have posted several entries to this blog that have covered various aspects of Db2 for z/OS high-performance DBATs (examples are entries posted in 2016 and 2013). Over the past couple of weeks, I have been working with a Db2 for z/OS administrator who is engaged in implementing high…
The Various Aspects of Db2 for z/OS Data EncryptionJust last week, a person on the Db2 for z/OS team at an organization asked me for some guidance regarding data encryption in a Db2 context. In responding to that request, I noted that Db2 for z/OS data encryption is a multifaceted topic, and I proceeded to describe various categories of Db2 data enc…
Db2 12 for z/OS Buffer Pools - Recommendations for PGSTEAL, PGFIX and FRAMESIZENot too long ago, I received a note from the leader of a Db2 for z/OS database administration team, asking for my take on a Db2 12 buffer pool configuration set-up that his team had devised. An interesting characteristic of the configuration was the use of the options PGSTEAL(NONE) and FRAMESIZE(2G)…
Clearing the Air Regarding Db2 12 for z/OS and "Deprecated Objects"On a number of occasions over the past several months, I have seen that there is some misunderstanding in the Db2 for z/OS community regarding support for certain types of database objects in a Db2 12 environment. Via this blog entry, I want to clear up these misconceptions. The misunderstandings t…
Db2 for z/OS Online LOAD REPLACE - Minimizing Impact on TransactionsA couple of years ago, IBM introduced an important enhancement for the Db2 for z/OS LOAD utility, via the fix for an APAR (the APARs are PI69095 for Db2 12, and PI67793 for Db2 11). This enhancement provided a capability that is popularly known as "online LOAD REPLACE," but is more formally referred…
Db2 for z/OS: Clearing Up Some Matters Pertaining to 10-Byte RBA and LRSN ValuesAt this time, many Db2 for z/OS-using organizations have already completed their migration to Db2 12. Others are still in the process of accomplishing that migration, or are finalizing migration plans. Especially at sites at which migration to Db2 12 is not yet a fait accompli, I have seen that ther…
Db2 for z/OS and RACF, Part 2: Db2-Internal SecurityIn the Part 1 post of this two-part blog entry, I described how RACF can be used to provide "external" security for a Db2 for z/OS system - external security being concerned with who (i.e., which IDs) can connect to the Db2 system, and how (e.g., in the form of a batch program and/or through CICS an…
Db2 for z/OS and RACF, Part 1: External Db2 Security In a Db2 for z/OS context, RACF (the IBM security management subsystem for z/OS systems) can serve two important purposes, providing security for a Db2 environment in an external and an internal sense. Db2 external security is about determining which users/processes can connect to a Db2 subsystem, a…