1. Chris Shaw CShaw@Xtivia.com @SQLShaw
Index Feng Shui
Chris Shaw
@SQLShaw

2. Rules of the Dojo Stop me and ask questions.
If it takes to long we may need to take it to a side bar.
Feel free to me
Scripts can be downloaded from my blog.

3. Sensei (About) CShaw@Xtivia.com 6 SQL Server MVP Awards
@SQLShaw
6 SQL Server MVP Awards
17 years of experience

4. Expectations
Use this session as a launching pad. There is a lot of information in here, and we don’t have time to cover all of it.

5. What is an index
Think of a book, if you are looking for Brain Surgery in a Medical book, where do you find the information you need?
Could the page numbers be considered an index?
Is the table of contents in the front of the book considered an index?
What if there wasn’t an index or a TOC? How long would that take?
Think about your MP3 player, is that an index?

6. B-tree
Root
Intermediate
Leaf

7. Primary Index Types Heap Clustered Indexes Non-Clustered Indexes
A Table without a clustered index
Clustered Indexes
All the data in sorted in the Leaf Node
Non-Clustered Indexes
Contains rows identified in the index other data is retrieved by a lookup.

8. Leaf Node
Heap
Clustered Indexes
Non-Clustered Indexes

9. Leaf Node
Heap
Clustered Indexes
Non-Clustered Indexes

10. Index Types and Strategies
Column Store
New in 2012
Modified in 2014
Covering
All the data you need is in the index
Filtered
Ability to remove rows that are not needed

11. Column Store Ideal for OLAP databases
New Index type in SQL Server 2012
Enterprise Edition
Non-Updateable
SQL Server 2014
Updateable

12. Column Store Data is stored by column not by row Data is non-clustered
Data is non-Unique

13. Covering Indexes Most often used to match specific Queries.
Select [Name], [City], [State], [Cell], [ ]
From Customers
Allows the index to return all required data without additional I/O
Big increase in performance
Easy to overuse

14. Covering Indexes

15. Filtered Indexes Allow indexing of only relevant data.
ex. Index only non-null data
Improves Maintenance Performance
Improved Storage
Improved Query Plans

16. Additional Index Terms
Selectivity
The unique quality of data in a row
Fill Factors
The percentage of data on a page
80% fill factor leaves 20% free space
0 and 100 % are the same or are they?
Page Splits
Seeks
Optimal use of the index
Scans (RBAR)
Analyzing each row.

17. Common Indexing Issues
Not being maintained -
Index is there just fragmented
As a table grows the search's slow
Demo - Fragmented Indexes
To much maintenance
Not enough Indexes
Slow Searches
Demo - Missing Indexes
To Many Indexes - When indexes hurt.
Slow Insert Statements
Demo - Demo Index Usage
Indexes that get you only half way there.
Book Mark Lookups

18. Entering the Zen
Best decisions are made with complete information. Gather information using:
DMV's
Query Plans
Performance Monitor
Statistics IO
Showplan_All

19. Demo

20. Maintenance Maintenance Plans
Difference between rebuild and re-organize?

21. Index FAQ Is the PK required to be clustered? What about Statistics?
How Often should I re-index.
What about online re-indexing?

22. Thank You
Questions
@SQLShaw