MySQL Forge

Resources for the MySQL Community

Categories: Contributing | Development | MySQLUniversity | Optimizer | Subquery Optimizations

New Optimizer Features in MySQL 6.0

Contents 1 New Optimizer Features in MySQL 6.0 2 Presentation 3 Questions 3.1 Questions asked before the session 3.2 Questions asked during the session 4 Voice recording and other links

← Back to MySQL University main page

[edit] New Optimizer Features in MySQL 6.0

• Date: 2007-09-21
• Presenter: Sergey Petrunia
• Scribe: Paul DuBois
• Attendees (please register by filling in your name below, and read the Instructions for Attendees):
  1. Max Mether
  2. Taylor Judd
  3. ...

[edit] Presentation

• The presentation: http://forge.mysql.com/wiki/Image:NewOptimizerFeaturesIn-6_0.pdf
• Additional slides from team exhibition: http://forge.mysql.com/w/images/5/53/HD2007-exhibition-NewSubqOptsIn5-2.pdf

[edit] Questions

[edit] Questions asked before the session

1. Can you explain what "semi" in "semi-join" refers to? "Semi" sounds like "partial," or "incomplete." Is it a partially done join?
   • No. Semi-join and inner join (aka just "join") are different operations. The difference is highlighted on slides #9 and #10. Also see Definition of semi-join in wikipedia.
2. SECOND_QUESTION
   • SECOND_ANSWER
3. ...
   • ...

[edit] Questions asked during the session

1. FIRST_QUESTION
   • FIRST_ANSWER
2. SECOND_QUESTION
   • SECOND_ANSWER
3. ...
   • ...

[edit] Voice recording and other links

• Voice Recording: Ogg Audio (25 min, 14MB)
• IRC log: IRC Text (5KB)

• Other resources:
  • http://s.petrunia.net/blog/?p=10: Subqueries: the new strategy for “NULL IN (SELECT …)”
  • http://s.petrunia.net/blog/?p=35: Observations about subquery use cases
  • http://forge.mysql.com/wiki/6.0_Subquery_Optimization_Benchmarks
  • http://forge.mysql.com/wiki/Subquery_Works
  • http://forge.mysql.com/wiki/6.0_Subquery_Optimization_Cheatsheet