Archives for July, 2013

What does it cost you to compress your data online?


Where there is often lots of info on compression available everywhere, it’s often much harder to find info what the cost is related to online vs offline page compression. So I did a test. I have a 10GB filegroup containing a 10GB heap on it (no indexes), data and log files have autogrowth set to […]

Check scheduler_id’s for parrallel queries using Extended Events


Trying to be good DBA’s, we followed the rule to set the maxdop = number of schedulers per NUMA node. I now want to check how often parallel queries can use different schedulers within the same NUMA node. Following scripts works fine for me. select DISTINCT session_id , scheduler_id from sys.dm_os_tasks WHERE parent_task_address IS NOT […]

Transactionlog lost


So what if you lose the disk that holds your transaction logs – and all database backup files. Of course, there is no DR plan available (if you put transaction log and backup files on the same disk, DR is clearly no priority). There are 3 options here Plan A: If your database was stopped […]