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June 21, 2018

Date Conversions, Tracing SQL Performance, & Listagg
In June we looked at date conversion issues, identifying the cause of slow SQL, dealing with ORA-01489 errors from listagg, and writing case expressions.

Key topics are at:

1:00 - Date conversion issues: implicit conversions; format masks; Gregorian to Julian calendar converion
10:15 - Why is my insert slow? An overview method for viewing SQL activity: SQL monitor, autotrace, and SQL trace; a discussion of blocking rows
30:55 - Dealing with listagg ORA-01489 errors: the on overflow truncate clause in 12.2; 12.1 pattern matching (match_recognize) solutions
49:55 - creating case expressions using formulas

Links in presentation:

How to Create an Execution Plan https://blogs.oracle.com/sql/how-to-create-an-execution-plan
Managing overflows in LISTAGG https://blogs.oracle.com/datawarehousing/managing-overflows-in-listagg

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Experts

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.