Database Blog

Oracle Performance Tuning — Trust but Verify

During an Oracle Performance Tuning engagement in the past, I learned a valuable lesson about validating the information that you are given during a database evaluation. About ten years ago, a client called me with a serious problem. They had just completed development on a new Oracle application at a large pharmaceutical company and the … Continue reading Oracle Performance Tuning — Trust but Verify

Oracle Performance Tuning: Periodically reorganize database objects

One of our Oracle Consultants shared a story with me today that illustrates the importance of periodically reorganizing objects in an oracle database. He was examining a performance problem with a very small oracle table. The table had only 154 rows!. Hardly a large table, and yet it was taking over a minute to do … Continue reading Oracle Performance Tuning: Periodically reorganize database objects

Oracle Security — Data Masking using Enterprise Manager

Database administrators often have to provide test data sets to developers, QA teams, or UAT teams. This can be done manually creating test data sets, which can take a very long time especially when the goal is to stress test a new system and a large amount of data is required. An alternative approach often taken by … Continue reading Oracle Security — Data Masking using Enterprise Manager

The importance of documentation, organization, and cross-training

A recent experience on a large database development project illustrates three very important principals to follow when developing a large computer system;  keeping code well organized, keeping code well documented, and ensuring that more than one person is familiar with all portions of the code base. After about four months of development the lead developer … Continue reading The importance of documentation, organization, and cross-training

Oracle Performance Tuning — Log Sync Waits

I recently worked with a client to resolve a significant performance issue related to painfully slow queries in an Oracle database. One of the queries that they wished to execute was taking over five hours to run. This is an Oracle 10g database running on a Solaris platform. The server has 8 processors so there … Continue reading Oracle Performance Tuning — Log Sync Waits

Five reasons why I avoid database query hints

I know that some will disagree with me on this but I have never been a fan of query hints.

Most database vendors give you the ability to override the query optimizer with hints that you specify in a query. Each query can be executed in a variety of ways by the…

Five reasons why I avoid database query hints

I know that some will disagree with me on this but I have never been a fan of database query hints. Most database vendors give you the ability to override the query optimizer with hints that you specify in a query. Each query can be executed in a variety of ways by the database engine. … Continue reading Five reasons why I avoid database query hints

Storing documents in a MongoDB database instead of the file system

We are currently working on an application that uses a mysql database. The application produces a large number of csv files that must be kept around for a few weeks, and then removed after being used in various ways by the users of the system. We need to keep track of all of these files and … Continue reading Storing documents in a MongoDB database instead of the file system