Do You Still Believe in Myths about SQL Performance?
In this session, I want to clear up some of the myths and rumors about performance optimization that still exist in the mind set of many developers and software architects. The participants can check for themselves how much they know about SQL query performance and which myths they still believe in.
During implementation of new applications, many developers don’t pay attention about performance in the database. The functionality of the application is important, but the efficiency of the SQL queries is often ignored. The DBA (or the Query Optimizer) will do the job later. If necessary, we can still create a few (or many) indexes, add hints or adjust database parameters. Anyway: in the Cloud, the Oracle database does everything automatically and autonomously.
Really? Unfortunately the reality looks different. Many performance problems are caused by a bad software design, unsuitable data models or inefficient SQL statements. Correcting such issues at the end of a project or when the system is already live, often needs a lot of effort. If a query works perfectly with 10 rows, but runs much forever with 100’000 rows, this problem cannot be fixed with a few configuration parameters.