Side-effect of mysqlhotcopy and LVM snapshots on active READ server

Saturday, September 26th, 2009 Posted in en_US, monitorização, mysql, performance | No Comments »

I just came across a particular feature of MySQL while using inspecting a Query Cache being wiped out at backup times. Whenever you run FLUSH TABLES, the whole Query Cache ... Read more..

Multiple field index vs external primary key calculation

Saturday, August 29th, 2009 Posted in en_US, mysql, performance | No Comments »

I bumped over a client which was using a VARCHAR(200) as a MyISAM PRIMARY KEY key for detecting colisions which was externally (by the app) calculated and fed into MySQL. ... Read more..

Percorrer uma tabela MyISAM de forma controlada

Wednesday, August 26th, 2009 Posted in mysql, pt_PT | No Comments »

Lembrei-me de partilhar um teste que fiz há tempos. O que se pretendia era demonstrar que podemos percorrer uma tabela MyISAM (e só neste caso específico) de forma controlada (ie, ... Read more..

The bigger smaller than the smaller one

Thursday, August 20th, 2009 Posted in en_US, mysql, performance | 4 Comments »

I was trying to determine if the storage size of a VARCHAR field in MySQL had any fixed influence in the key size. I've created a few tables, but an ... Read more..

MySQL DATETIME vs TIMESTAMP vs INT performance and benchmarking with MyISAM

Monday, July 6th, 2009 Posted in en_US, mysql, performance | 9 Comments »

Recently there was a discussion about DATETIME vs TIMESTAMP vs INT performance and storage requirements. If one setup was bound to disk usage, one would expect INT to perform better, ... Read more..