At the Percona engineering team, we often receive requests to analyze changes in MySQL/Percona Server for MySQL behavior from one version to another, either due to regression or a bug fix (when having to point out to a customer that commit X has fixed their issue and upgrading to a version including that fix […]Read more
Lately, I worked on several queries which started returning wrong results after upgrading MySQL Server to version 5.7 The reason for the failure was derived merge optimization which is one of the default
optimizer_switch options. Issues were solved, though at the price of performance, when we turned it
OFF . But, more importantly, we could […]
Welcome to another post in our series of interview blogs for the upcoming Percona Live Europe 2017 in Dublin. This series highlights a number of talks that will be at the conference and gives a short preview of what attendees can expect to learn from the presenter.
This blog post is with Charity Majors, CEO/Cofounder […]
Welcome to MySQL QA Episode #6!
Today we will look into analyzing and filtering our QA run. We’ll use tools like pquery-prep-red.sh, pquery-clean-known.sh & pquery-results.sh
1. Quick re-cap and QA run setup
5. Bonus: pquery reach – pquery-reach++.sh
We’ll also introduce the text_string.sh tool which extracts a most-specific text string from the error log in order […]
Welcome to MySQL QA Episode #5! In this episode we’ll be setting up and running pquery for the first time… and I’ll also trigger some actual bugs (fun guaranteed)! I’ll also introduce you to mtr_to_sql.sh and pquery-run.sh.
pquery-run.sh (the main wrapper around pquery) is capable of generating 80-120 MySQL Server crashes – per hour! See how […]