Almost a year ago, I started a spotlight feature that I sadly haven't followed through on in a while so there is no time like the present! I met Ric Van Dyke when he was part of the Hotsos team that came into our offices several years ago to diagnose our performance problems and teach our group how to avoid them in the future. Imagine my surprise and delight when I found his blog after I attended the Hotsos Symposium in 2012!
Flash forward a few years and here we are! The first article I want to share is his latest about HASH_VALUE and PLAN_HASH_VALUE, as it has some "basic" information which is nonetheless important to have in our quest for complete knowledge about the Oracle database. Aside from the history of the feature, which is great as I am getting into this a bit late, Ric proves out the fact that two similar SQL statements that are written differently actually can share the same PLAN_HASH_VALUE but have different HASH_VALUEs. Additionally, he helps us remember another tool we have available to do troubleshooting and diagnosis of SQL plans!
I thought this was a great example of the articles that Ric writes, and I hope you'll enjoy the week long spotlight on his blog!