Lockwood Lyon

Applications running with dynamic SQL are ever-increasing. Without some methods to contain the onslaught of queries, performance drops and phone calls increase. What can a DBA do to remain sane and avoid a visit from the head of IT? This article addresses common issues encountered in performance of applications containing dynamic SQL, and how to […]

For the DB2 for z/OS professional the two most common systems tuning scenarios are tuning a DB2 data sharing group or tuning a series of application SQL statements. The data sharing group environment can involve multiple hardware installations and many other cross-system features and functions such as coupling facilities and management policies. Resource constraint analysis […]

Many DBAs and analysts are confused by the variety of serialization mechanisms used by IBM DB2 for z/OS to ensure data consistency and maintain concurrency control. Understanding logical and physical locking can help you better understand and improve application and system performance. The word lock conjures up visions of DB2 holding tightly to a resource […]

Function use is common in IBM DB2 SQL. However, use and misuse of functions can affect query access paths and performance. Here are a few tips to help you tune IBM DB2 queries and avoid using functions that consume precious CPU resources. Most of the common functions fall into two groups: scalar functions and aggregate […]

When involved in application performance tuning, the database administrator usually concentrates on reducing elapsed times or I/O waits. Too often, the CPU is forgotten, perhaps because of recent advances in CPU speeds, parallelism, and specialty processors. Regrettably, disregarding CPU costs can lead to resource contention, wasted CPU cycles, and more frequent hardware upgrades. The DBA […]

In the spirit of David Letterman’s Top Ten lists, here is a look at what IT management requires from database management systems (DBMSs). 10. Interoperability With budgets shrinking, IT must sometimes look to multiple vendors for outside software, hardware, and staffing solutions. All these people and processes must work together. This includes fast, transparent data […]

Many critical business applications now execute in an environment separate from that of the enterprise database server. The database administrator often finds monitoring and performance tuning of these “distributed” applications to be especially difficult. This article looks at common performance issues of distributed applications and presents advice to assist the IBM DB2 database administrator in […]

We are finally getting back to where we should be: designing databases right the first time. There is, however, a small problem: What do we do with current implementations? How do we backfill quality into them? In the context of database design what does quality mean? Defect prevention during design Defect detection and remediation during […]

Database management systems (DBMSs) have simultaneously simplified and complicated the lives of many IT workers. Error codes passed from the database back to the application can take on more than 1000 values. What level of error checking should developers include in applications? Gone are the days of file processing. In the past, it was enough […]

A load test gives the database administrator quite a lot of valuable information and may make the difference between poor and acceptable application performance. Here are some proactive tips to make your IBM DB2 production implementation a success. Many software development projects produce software that moves into the production environment without a formal load test. […]

Of the various constraints possible on relational tables, referential constraints are perhaps the most common … and most misused. Learn about the advantages and disadvantages of different methods to implement and enforce RI, and issues that must be addressed when implementing DBMS-enforced Referential Integrity. Of the various constraints possible on relational tables, referential constraints are […]