Monday, 11 August 2014

SQL 2012 Wait Type : Dirty Page Poll

Whilst running some tried and tested scripts to look at wait types, I came across one I had not seen before. It is a background thread that looks to see if there are dirty pages that need to be flushed to disk. Given I found it on a barely used test box, I was not worried.

To quote the ToadWorld site, 'It is a benign wait type and shouldn’t be any concern if you happen to see high values for this wait type on your systems'.

Toadworld : Dirty Page Poll Wait Type in SQL 2012

Thursday, 7 August 2014

Adventureworks : Large Sample Database

A colleague wanted a 'large database' (he didn't care what) for testing perfomance of a backup solution. Given privacy, security, ethics etc prevent me from parting with a genuine database and creating mock/random data is time consuming I was faced with an issue.

Creating an empty database and simply sizing the files wouldn't work as the backups would be highly compressable i.e would be minuscule. Likewise the data compression that I've applied to my backups by default also needs to be off.

I recalled seeing a tweet about a custom version of AdventureWorks and after a short search I found Enlarging the AdventureWorks Sample Databases. This script adds random data, increaing the size of AdventureWorks by creating SalesOrderHeaderEnlarged and SalesOrderDetailEnlarged tables. It can also easily be adapted to create larger datasets (Hint : Increase the number of UNIONed tables in the derived table).