SQLBits 2011

The Art of War-Fast Track Data Warehouse & Fragmentation

When loading a Fast Track Data Warehouse it is important to ensure that your data is optimally laid out for Sequential I/O. Fragmentation is therefore the enemy. Know your enemy. Learn what it is, how it occurs and prevent it from happening to you!

When loading a Fast Track Data Warehouse it is important to ensure that your data is optimally laid out for Sequential I/O. Fragmentation is therefore the enemy.

Know your enemy.

Learn all about fragmentation - from the inside out. Let's get back to brass tacks and understand how SQL Server handles heaps and clustered indexes, re-visit page allocation and then apply this knowledge to our understanding of fragmentation. We will conclude by looking at some design patterns to help you minimise the impact of fragmentation on your next data warehousing project.

Key topics presented:

  • Logical, extent and file fragmentation
  • Heap and clustered index architecture and internals
  • Page allocation - how it works and how to influence it
  • Trace flags that help avoid fragmentation
  • Fragmentation in action
  • Design patterns for minimal fragmentation