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August 9, 2018

Update, Merge, & Polymorphic Table Functions
In August's hot, summery session Chris Saxon and company looked at:

1:45 - Updating a query; why this can lead to ORA-01779 errors
4:20 - Correlated updates; the need for existence checks; performance impact
8:00 - Merge; update only merges; performance advantage over correlated updates
24:35 - 3rd Normal Form; identifying 3NF violations; how to fix
29:30 - Hiding table changes with views; instead of insert triggers; changing with minimal code impact
48:45 - Polymorphic table functions; what they are; how to write one; example package to add columns

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Your Experts
Chris Saxon
Chris Saxon, Oracle Developer Advocate for SQL    
Chris Saxon is the quizmaster for the Database Design competitions and an Oracle Developer Advocate for SQL. His job is to help you get the best out of the Oracle Database and have fun with SQL! He's also part of the answer team on Ask TOM and creates YouTube videos at The Magic of SQL channel.
Keith Laker
Keith Laker, Senior Principal Product Manager    
I have been working with Oracle data warehouse technology for over 20 years working on a wide variety of data warehouse projects both as a consultant and an onsite support engineer. I am now part of the Data Warehouse Product Management Team where I am responsible for analytical SQL. I am based in the UK at our Manchester office. A key part of my role is to work with our sales teams to brief our customers on data warehousing and analytical SQL: explaining the wide variety of new and exciting opportunities that our DW and analytical solutions can support. I regularly deliver sales training for data warehousing and analytical SQL across all our sales regions and provide competitive intelligence support across all the major data warehouse vendors.