Comparing Expression Lists (not tuples)

This post is a long-winded answer to a question Bryn Llewellyn asked me on Twitter about comparing expression lists.

#OUGN17 Row Pattern Matching with MATCH_RECOGNIZE

OUGN17 (the boat conference) rocked - and the boat didn't, thank goodness. I gave two talks about row pattern matching that were well received: two or three brave souls even went to both talks. I put my slides on the OUGN Google Drive page and on Slideshare.

Multi-Table Inserts with Sequences

Multi-table inserts are a drag when sequences are involved, because we don't have enough control over when the sequence is incremented. I've seen some dangerous workarounds. Here is a workaround that I think is safe.

Disappearing Data

Did you know that Oracle DML can silently change data you want to put into the database? A recent twitter discussion started by Martin Widlake (@MDWidlake) prompted me to study more closely what happens when.

#UKOUG_Tech16: Ranges, Ranges Everywhere

I presented this topic on at Tech 16 on Monday afternoon. The latest version is on the Tech 16 website and on Thanks to the organisers, staff, presenters and delegates who made this a great conference and a wonderful experience!

#UKOUG_Tech16: Advanced Row Pattern Matching

I presented this topic on Super Sunday. The latest version is now on the Tech16 site and on

#DOAG2016: Bug !

I did it: in my proudest moment at DOAG2016, at the very end of my second presentation, I presented a brilliant SQL query with a bug in it. After agonizing for awhile, I finally saw that the correction was simple and didn't change the timing.

#DOAG2016: Ranges, Ranges Everywhere!

Today I did my second presentation at DOAG2016. It was at 9:00 so I got to sleep in ;) The room was huge but there were enough people that I didn’t feel too lonely. The room and the technical help were top notch, and again there were questions at just the right time to remind me […]

#DOAG2016: Advanced Row Pattern Matching

DOAG2016 started today at 8:30, and I did too. There were so many great presentations at the same time as mine, I was surprised and pleased to get a nice audience.