Some Important Points from “SQL Misconceptions” Session from Pinal Dave and Vinod Kumar

Posted on March 21, 2012 by Dhananjay Kumar — 7 Comments ↓

I attended session of Pinal Dave and Vinod Kumar on SQL Misconceptions. Few of points from that session is as following

SET ROWCOUNT and TOP and OrderBy is not same.
Set RowCount , Top and OrdetBy gives different execution plan
Misconception is Cluster Index gives the result out in Order. It sort and gives result
Seems due to parallelism Cluster Index does not gives result in order
Cluster Index assure u sorted result only if you are explicitly using order by in the query
Precision of small DateTime 31 sec rounded to next minute and 29 sec gets truncated to orevious minute
As of textbook cluster index physically store the data.
Cluster Index does not store in physical order
Go 10 will run 10 times
In simple recovery model your transaction log is as big as longest transaction run in the system.

I hope this quick post is useful. Thanks for reading.

Dhananjay Kumar is Developer, Blogger , Speaker, Learner , Mindcracker & Microsoft MVP.

pinaldave says:

March 21, 2012 at 11:37 pm

Thank you Dhananjay for this excellent list. Wow – you really paid attention to details.
Vadivel says:

March 22, 2012 at 8:15 am

Nice points. Just thought would share the blog post which I did last year on “Does Clustered Index physically orders the data within a table? – http://vadivel.blogspot.in/2011/09/does-clustered-index-physically-orders.html

–Vadivel
MVP SQL Server
Vinod Kumar M (SQL) (@vinodk_sql) says:

March 24, 2012 at 10:54 am

Thanks for doing one of a kind thing at #TechEdIn. This is was an awesome experience to see the love and support. Thanks …
Dhananjay Kumar says:

March 25, 2012 at 5:17 pm

thank u sir