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October 20

14:00 UTC   Start Times Around the World

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Finding the Longest Common Substring and Gestalt Pattern Matching
In this session Stew Ashton joins Chris Saxon to discuss a recent question on Ask TOM: implementing the Ratcliff-Obershelp similarity algorithm to rank how similar two strings are.

This works by recursively finding common substrings in the source words. Stew and Chris discuss how to do this using SQL and PL/SQL, comparing the performance of various solutions to find the fastest method.

The winner may surprise you (hint it's not SQL).

Your Experts

Chris Saxon
Chris Saxon, Oracle Developer Advocate for SQL    
Chris Saxon is an Oracle Developer Advocate and quizmaster on Dev Gym. 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.
Stew Ashton
Stew Ashton,    
Stew is one of the top SQL developers in the Oracle community, to which he has contributed for several years through the AskTom site, the OTN/ODC forum dedicated to SQL and PL/SQL, and his blog. He is also an award-winning conference speaker. Stew has been a developer and application architect for 35 years, working in mainframe, client-server and web architectures. Since 2005 he has focused on proper use of the Oracle database in OLTP applications and batch processing, often improving performance up to 300-fold.