Total System Failure: Why you should validate your database backup
Every now and then things happen that make us realize how important double checking things can be. I had a recent experience in which four unrelated parties (including me) did the wrong thing regarding one business transaction. If any one of us had done the right thing, there would have been no problem. But all […]
Database Downtime: Prepare For The Unexpected
Test your Assumptions: Database Backup and Recovery Every now and then something happens that really drives home the need to test and validate the assumptions that we have about the availability of our IT assets. I had an experience this week that brought to mind the importance of testing backup and recovery and business continuity plans. […]
Query Rewrite: What is MySQL Doing To My Queries?
The Impact of Query Rewrite on MySQL Query Optimization When processing a query, every relational database vendor takes a number of similar steps to parse, validate, and optimize a query. MySQL does the following: Validates the query syntax — does it use valid operators, are the clauses in the proper order, etc. Validates the query […]
Advantages and Disadvantages of Disk-Based Backup and Recovery
Data Backup Advantages & Disadvantages While tape-based backup approaches may still be optimal for long-term data retention, more and more database storage/backup administrators are moving from tape to disk technology for everyday data backup and data recovery. This is not surprising as disk is faster to write to and faster to recover from, as well […]
Five Leading Causes of Oracle Database Performance Problems
As we evaluate our clients’ Oracle databases and help them solve problems relating to performance and stability, we see many causes for these issues. However, there are a small number of basic issues that tend to cause problems on the majority of systems. Our Tech Tips document describes these issues and discusses methods of identifying them and resolving […]
Remove that Clutter: The Annual Database Security Audit and Cleanup
As the New Year begins, many of us take the beginning of a new calendar year as a cue to to clean out and shred our old files and reorganize our storage spaces so that we have room for all the new supplies and equipment we will need in the new year. We do this […]
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 […]
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 […]
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 […]