VirtualBox Hyper-Threading Benchmark Surprise
I needed to ensure good CPU and memory performance in a VirtualBox virtual machine running on a 4-core desktop, and googling didn’t provide any clear guidance. After some benchmarking, the surprise came in the shape of consistently getting the best result when ignoring VirtualBox’ warning on oversubscribing processors: As always, these results are only valid […]
Tip: Open QlikView Without Data in Windows Explorer
I often use the Open ‘MyQVW’ Without Data option in Recently Opened Documents: This is especially useful for quickly looking at the script or UI of very large QVWs, without having to wait for all the data to load (if you can open it at all away from your server!) My trivial (but I find […]
QlikView Horizontal Table Issue with +40 Fields
I discovered the following issue with Horizontal tables (Straight Table > Properties > Presentation > Horizontal) in the AJAX ZFC client: The chart only displays the first 40 fields; any further fields added beyond the first 40 are not displayed. Fields beyond 40 are exported to Excel OK, and also work perfectly fine in the […]
SMO + LINQ for Entity Framework Code First Database Modifications
Database Aspects of Code First Using Entity Framework (EF) 4.1 with the Code First approach seems like a good choice for my greenfield Web App – during development I can focus on the Web and C# .Net paradigms, and postpone the bulk of the database work until such time my application and data model has […]
GOTCHA: SQL Server changes query plan without changing plan_handle
Or how to efficiently get at old query plans Performance Tuning Mission While on a SQL Server 2008 Data Warehouse performance tuning mission, this aspect (or undocumented gotcha as it felt like at the time) of the query plan Dynamic Management Functions caused some head scratching, until I sussed that: A query plan can change […]
Previously on Kristian Wedberg: Data Warehouse and BI articles
Just to have things nicely gathered in a single place, I’ll kick my new blog off with a few links to my earlier blog & articles, where the content is still relevant: SQL Server Central articles Generating Test Data with Integration Services SSIS – Code Reuse and Complex Control Flows SSIS – Reusable Benchmark Harness […]
