Tim Mitchell

Tim Mitchell is a business intelligence consultant, author, and trainer. He has been building data solutions for over 20 years, and is a 13-time recipient of the Microsoft Data Platform MVP award (2010-2022). He is the founder and principal data architect at Tyleris Data Solutions.

Tim has spoken at international and local events including the SQL PASS Summit, SQLBits, SQL Connections, along with dozens of tech fests, code camps, and SQL Saturday events. He is the author of the book The SSIS Catalog: Install, Manage, Secure, and Monitor your Enterprise ETL Infrastructure, coauthor of the book SSIS Design Patterns, and is a contributing author on the charity book project MVP Deep Dives Vol 2.

You can visit his website and blog at TimMitchell.net or follow him on Bluesky at https://bsky.app/profile/tmitch.net.
  • Interests: SQL Server, Data Warehousing, ETL, Data Architecture, Python, Dbt

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Blog Post

SSIS Parameters

SSIS parameters help to ease the process of passing runtime values to SSIS packages. For values that can change over time, using parameters in SSIS is an ideal means...

2020-07-14 (first published: )

480 reads

Blog Post

Secure Your Data Prep Area

I’ve been building ETL processes for many years, and I’ve learned two universal truths: data preparation is messy, and you must always secure your data prep area. A data...

2020-06-18

4 reads

Blog Post

Lessons from Iowa’s Caucus Debacle

Earlier this week, the state of Iowa held its caucuses to choose each political party’s nominee for November’s presidential election. Being the first state in each election cycle to...

2020-02-11 (first published: )

786 reads

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Blogs

Why Optimize CPU for RDS SQL Server is a game changer

By

One feature that I have been waiting for years! The new announcement around optimize...

Performance tuning KubeVirt for SQL Server

By

Following on from my last post about Getting Started With KubeVirt & SQL Server,...

T-SQL Tuesday #193 – A Note to Your Past, and a Warning from Your Future

By

I haven’t posted in a while (well, not here at least since I’ve been...

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Forums

Refactoring SQL Code

By Steve Jones - SSC Editor

Comments posted to this topic are about the item Refactoring SQL Code, which is...

The Read Committed Snapshot Isolation behaviour

By Alessandro Mortola

Comments posted to this topic are about the item The Read Committed Snapshot Isolation...

Working with JSON/JSONB Data in PostgreSQL using Python

By sabyda

Comments posted to this topic are about the item Working with JSON/JSONB Data in...

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Question of the Day

The Read Committed Snapshot Isolation behaviour

I am currently working with Sql Server 2022 and AdventureWorks database. First of all, let's set the "Read Committed Snapshot" to ON: 

use master;
go

alter database AdventureWorks set read_committed_snapshot on with no_wait;
go
Then, from Session 1, I execute the following code: 
--Session 1
use AdventureWorks;
go

create table ##t1 (id int, f1 varchar(10));
go

insert into ##t1 values (1, 'A');
From another session, called Session 2, I open a transaction and execute the following update: 
--Session 2
use AdventureWorks;
go

begin tran;
update ##t1 
set f1 = 'B'
where id = 1;
Now, going back to Session 1, what happens if I execute this statement? 
--Session 1
select f1
from ##t1
where id = 1;
 

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