Nice talk. DB Performance is still a bit of a mystery to me. I usually log the times that each query takes and if they are long, then I’ll point them to an expert like yourself. At least I will know who to ask for advice next time I write a horribly slow DB query ))
@Kabutz, yes please feel free. Rather than manually logging the times, it would be more convienient – and helpful for the ‘expert’ – to generate a database level trace. Here is how to do that:
With P6Spy, you have a JDBC driver that logs the times automatically. The beauty is that it is database independent, so I can apply the same technique whether the customer is using Sybase, DB2, Oracle, MySQL, etc. Once we have discovered that the database is indeed a bottleneck, we would pass that information to someone like you who can then run a detailed trace. Thanks for the link for Oracle though
I found your session quite informative, i want to learn how explain plan works and how can I understand explain plan and the terminology used in it, to tune my code. is this something you can help? any article ? book ? examples ?
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[...] the video tutorial here if you haven’t [...]
Nice talk. DB Performance is still a bit of a mystery to me. I usually log the times that each query takes and if they are long, then I’ll point them to an expert like yourself. At least I will know who to ask for advice next time I write a horribly slow DB query
))
Heinz
@Kabutz, yes please feel free. Rather than manually logging the times, it would be more convienient – and helpful for the ‘expert’ – to generate a database level trace. Here is how to do that:
http://repettas.wordpress.com/2008/09/19/oracle-10046-trace-for-new-users/
With P6Spy, you have a JDBC driver that logs the times automatically. The beauty is that it is database independent, so I can apply the same technique whether the customer is using Sybase, DB2, Oracle, MySQL, etc. Once we have discovered that the database is indeed a bottleneck, we would pass that information to someone like you who can then run a detailed trace. Thanks for the link for Oracle though
Hi Hardeep,
I found your session quite informative, i want to learn how explain plan works and how can I understand explain plan and the terminology used in it, to tune my code. is this something you can help? any article ? book ? examples ?
From this blog I can suggest http://blog.hardeep.name/computer/programming/20090224/sql-tuning-ref/ and http://blog.hardeep.name/wp-content/uploads/2009/07/performance_tuning_guide.pdf
If you are interested further, I suggest this book: http://books.google.com/books?id=Ifdbua6o4agC&lpg=PP1&dq=book%20oracle%20sql%20performance%20tuning&pg=PP1#v=onepage&q=book%20oracle%20sql%20performance%20tuning&f=false