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Displaying posts with tag: innodb_stats_auto_recalc (reset)
On InnoDB's Persistent Optimizer Statistics

As I put it in recent Facebook post, one of MySQL features that I truly hate is InnoDB's persistent statistics. I think I should clarify this statement. It's great to have a way to save statistics in between server restarts, to have better control on the way it is estimated (even on a per table basis), set it explicitly, check it with simple SELECT. These all are great additions since MySQL 5.6.2+ that I truly appreciate (even if I may not be happy with some implementation details). They helped to make plans for queries against InnoDB more predictable and allow (with some efforts applied) MySQL query optimizer to really work as "optimizer" instead of "randomizer" or "pessimizer" (as some people called it) for InnoDB tables.

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Recalculating InnoDB Persistent Statistics - a Story of the Bug Report

One of the first posts in this blog was about reporting MySQL bugs "properly", in a way that maximizes chances for it to be processed really soon. I had written the following there:
"Ideally, you should provide a complete test case and/or instructions that any reader can use to reproduce your problem"Indeed, if one can just copy/paste something to mysql command line client or run some file attached to see the problem, chances are high for the bug to be processed really soon. We all like to get low hanging fruits from time to time, and Oracle engineers who work on bugs are not exceptions. But does this mean that bug without clear test case has no value and is going to be ignored?

It should NOT be the case. Let's review Bug #70617 reported by my …

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