Db2 One Way Hashing as a Data Masking Solution

Database performance is heavily influenced by data volume and cardinality (or how unique that data may be).

It’s interesting to watch the look on someone’s face when this concept clicks. There is a look of understanding from a developer when she can extrapolate why SQL ran in seconds on a small, local, dockerized, database but the same SQL runs in minutes in a much larger QA environment.… Read the rest

Continue reading »

Reducing Contention: Changing Default Isolation Level for Websphere Commerce (WCS)


The Problem

I often lean on analogies when I speak to non-technical people about technical topics. For example, I would explain database locking as “two kids fighting for the same candy bar”.  If you introduce isolation levels into the conversation, I would expand the analogy to include “one sibling holding on to a candy bar they care nothing about just because they don’t want the other sibling getting to it”.… Read the rest

Continue reading »

Query Performance Analysis

Some of the more complicated work a DBA does is often analyzing a query. Whether it is proactive or in response to a performance problem, there are so many factors that go into query performance. Even when looking at a query that has a performance problem, there is only occasionally a single, obvious cause for all of the problems.… Read the rest

Continue reading »

Comparing dsmtop and db2top

dsmtop is a long-awaited refresh of the wildly popular db2top. Like db2top, dsmtop is a free tool, included with DB2. It is in the base DB2 install starting with 11.1, and can be installed on DB2 10.1 or 10.5.

History of db2top

As I personally recall, db2top first came out of IBM AlphaWorks.… Read the rest

Continue reading »