Nobody complains that the database is too fast. But when it is s-l-o-w people trying things that maybe the should not. Add an index and things are great for a short while before they get slower. Or you want to try a histogram but have no clue where to start. This talk is an explanation of how indexes really work, why histograms are great for some types of data, how to examine a query plan (what the database optimizer wants to execute to get your data), and why the optimizer can be easily fooled into making bad choices. Plus you will get introduced to some other ways of making your queries run faster.
What you'll learn from this talk:
- What is a histogram and what is used for.
- How indexes really work in MySQL
- Why the MySQL optimizer is like a GPS and why old information can skew performance