I already wrote in the blog as well mentioned in presentation there is often a choice you have to make between having prefix index – which can be significantly smaller in size and having index being covering index, which means query can be executed using only data from the index without reading the row […]Read more
I was restarting MySQL on box with 50.000 of Innodb tables and again it took couple of hours to reach decent performance because of “Opening Tables” stage was taking long.
Part of the problem is Innodb is updating stats on each table open which is possibly expensive operation, but really […]
In query examinations it is often interesting which columns query needs to access to provide result set as it gives you ideas if you can use covering indexes to speed things up or even cache some data by denormalizing tables. So far it has to be done manually – look at SELECT clause, […]Read more
Running RPM based or other packaged MySQL Binary you may have a problem if you would like to rebuild binary for some reason – change some build settings, apply some third party patches or simply try latest snapshot (This time I was both applying patches for Innodb scalability and Vadim’s patches to get […]Read more
I was pretty busy last month with project which will be annonced very soon (I hope), but I can’t miss bug fix
of my favorite bug 15815. I wrote about this problem before and also investigated in my presentation.
Finally bug fix was pushed into 5.0-bk tree and now I have it in my hands.
Let me […]