I'm currently working on a MySQL database where we are seeing a large number of invalidations from the query cache, primarily because of the high number of INSERT, DELETE and UPDATE statements that ...
I just started dabbling with the query cache for our CMS. Can anyone tell me (or at least give a good guess) why I get a lot of Qcache_lowmem_prunes when more than half of Qcache_free_memory is free? ...
So we had a long running proc causing problems this morning (30 sec + run time). We decided to check to see if parameter sniffing was to blame. So, we rewrote the proc and set the incoming ...
Before running a performance test / baseline for an app that uses SQL Server, I want to be able to set the instance to a "clean" state, without restarting the instance. There are steps I tend to ...
Is there a way to find out how much memory a table is taking up in SQL Server (2005 and greater)? For example, suppose I have a table with 30 million records. I'd like to know how many pages ...
Currently I run DBCC FREEPROCCACHE when I want to wipe information out of the buffer pool between running SQL queries. However, I was reviewing this Technet article referencing DBCC FREESYSTEMCACHE. ...
We are having an annoyance with our PHP/MySQL site in that it seems to cache data from the database and our PHP pages are showing out of date records. In fact, there are pages that link to URLs that ...
On each page of my websites 2 or 3 permissions have to be checked and I use role-permission model. Which one is better? to check permissions of each user always through database directly or once ...
Maybe it sound's like i'm an idiot... But i'm developing app with huge db on RoR. Also i see that if i do some query and after that do it one more it is doing much faster, becouse it has been ...