In this blog we are going to see some basic things on how to interpret a execution plan for a query . The first first step on enhancing a query for optimal performance is to understand the query execution on cost basis , which part of the of the query is costly and which part is not . To do so, SQL Servers query execution plan is the best choice, by which we can point out which part of our query is more costlier.
Learning a query execution plan is like learning a new language, which is iconic language. Just explaining each and every icon of this language will be wage for you. More things on execution plan can be garbed while practicing it .
Before dive deeper into the subject , we should know the limitations of the execution plan. Execution plan doesn’t tell you below things
- Locks acquired
- Wait statistics
- Data is in the cache or not
- Not a replacement of SET STATISTICS IO
- Not a replacement of SET STATISTICS TIME
Below are some easy usage ways to get full benefit of the execution plan
“We have to read the execution plan from right to left and from down to top”.
I am using AdventureWorks2008 database on my examples. In this blog we will see only some basic things and spice up things on the coming series
