Over the past few years, I've been making notes on pgsql-performance postings, specifically those postings which relate to query performance issues. Today, I gave a talk at PGCon on the data I've been able to gather.
If you attended the talk, please leave feedback through the PGCon web site or feel free to leave a comment below with your thoughts. If not, you can find the slides on my Presentations web page. A few people asked me to post the raw data on which the talk was based, including links to the original threads. I have created a Query Performance section on my Google Site and posted the information there.
The version posted on the web site incorporates a few minor corrections as compared to what I presented in the talk; and I have left out (for the sake of politeness) the cases I attributed to user error. There were actually only 2 such cases, not 3 as I said in the talk, but either way it seems more polite not to post specific links. Please contact me if you find other mistakes in what I have posted and I will correct them.
Many thanks to all those who said nice things about my talk!