SQL Database Engine Blog
This is the blog of the engineering team managing and developing the Database Engine for SQL Server and Azure SQL Database
A Unicode Compression example
Now that we have Unicode compression available in SQL Server 2008R2 as described in, let me take a...
Author: Sunil Agarwal Date: 08/16/2009
Unicode Compression in SQL Server 2008R2
In my previous blog, I had mentioned that unicode compression will be available as part of next SQL...
Author: Sunil Agarwal Date: 08/16/2009
Customer feedback on Data Compression
As I described in my previous blog, the data compression feature has been very successful. We do...
Author: Sunil Agarwal Date: 08/16/2009
Update on data compression performance/space-savings and links to published white papers
It has been a while since I blogged about data compression so I thought it will be good to provide...
Author: Sunil Agarwal Date: 08/16/2009
TempDB Monitoring and Troubleshooting: Out of Space
One of the key challenges in TempDB is that it is a common resource for all applications running on...
Author: Sunil Agarwal Date: 01/11/2009
TempDB Monitoring and Troubleshooting: DDL Bottleneck
This blog continues the discussion on the common issues in TempDB that you may need to troubleshoot....
Author: Sunil Agarwal Date: 01/11/2009
TempDB Monitoring and Troubleshooting: Allocation Bottleneck
This blog continues the discussion on the common issues in TempDB that you may need to troubleshoot....
Author: Sunil Agarwal Date: 01/11/2009
TempDB Monitoring and Troubleshooting: IO Bottleneck
I hope my earlier blogs on TempDB...
Author: Sunil Agarwal Date: 01/04/2009
Managing TempDB in SQL Server: TempDB Configuration
In my previous blogs, I described the types of objects in TempDB and how they are managed. I hope...
Author: Sunil Agarwal Date: 01/04/2009
What is allocation bottleneck?
Allocation bottleneck refers to contention in the system pages that store allocation structures....
Author: Sunil Agarwal Date: 01/04/2009
Managing TempDB in SQL Server: TempDB Basics (Version Store: Growth and removing stale row versions)
In the previous blog...
Author: Sunil Agarwal Date: 12/31/2008
Managing TempDB in SQL Server: TempDB Basics (Version Store: logical structure)
Now that we know a few things about Version Store, let us now look into its structure to understand...
Author: Sunil Agarwal Date: 12/31/2008
Managing TempDB in SQL Server: TempDB Basics (Version Store: Simple Example)
In order to understand the version store, let me start with an example. I will use a database that...
Author: Sunil Agarwal Date: 12/30/2008
Managing TempDB in SQL Server: TempDB Basics (Version Store: Why do we need it?)
Version store is a new entity in SQL Server 2005. It is used to store versions of data and index...
Author: Sunil Agarwal Date: 12/21/2008
Managing TempDB in SQL Server:TempDB Basics (cont..)
In the previous blog...
Author: Sunil Agarwal Date: 12/21/2008
Managing TempDB in SQL Server
Over past few of years, I have given TempDB presentation in many conferences and the feedback that I...
Author: Sunil Agarwal Date: 12/21/2008
DML operations on a HEAP and compression
In my previous blog...
Author: Sunil Agarwal Date: 12/21/2008
Enabling compression on a HEAP
I often get a question how to do enable compression on a table that is a heap (i.e. it does not have...
Author: Sunil Agarwal Date: 12/19/2008
New update on minimal logging for SQL Server 2008
Based on the customer feedback, we have decided to make minimal logging functionality into a...
Author: Sunil Agarwal Date: 10/23/2008
Does data compression lead to more fragmentation?
Lately I have been asked how data compression impacts fragmentation (i.e. does it cause more or less...
Author: Sunil Agarwal Date: 08/06/2008
Enabling FILESTREAM post SQL2008 Setup - a Known Issue in SQL Config Manager
In SQL Server 2008 Feb CTP, there is a bug in the WMI provider for FILESTREAM, inside SQL...
Author: OmelJ - MSFT Date: 06/09/2008
TempDB:: Table variable vs local temporary table
As you know the tempdb is used by user applications and SQL Server alike to store transient results...
Author: Sunil Agarwal Date: 03/30/2008
Overhead of Row Versioning
Last week I was teaching a class on snapshot isolation and we discussed the overheads of snapshot...
Author: Sunil Agarwal Date: 03/29/2008
CHECKSUM and Tempdb
You may recall that starting with SQL Server 2005, you have an option available to enable CHECKSUM...
Author: Sunil Agarwal Date: 03/23/2008
Minimal Logging changes in SQL Server 2008 (part-3)
So far we had discussed...
Author: Sunil Agarwal Date: 03/23/2008
Minimal Logging changes in SQL Server 2008 (part-2)
In the previous example...
Author: Sunil Agarwal Date: 03/23/2008
Minimal Logging changes in SQL Server 2008
Please refer to the earlier post for the background information on minimal logging. Starting with...
Author: Sunil Agarwal Date: 03/06/2008
FILESTREAM Configuration and Setup Changes in SQL Server 2008 February CTP
FILESTREAM is disabled by default in SQL2008. Before you can start to use FILESTREAM, you must...
Author: OmelJ - MSFT Date: 03/03/2008
Example: Index fragmentation with insert/updates, measuring it and fixing it
This blog shows a very simple example to illustrate data fragmentation, measuring it, seeing behind...
Author: Sunil Agarwal Date: 02/29/2008
Bulk Import Optimizations (Minimal Logging)
In the previous blog I had listed all bulk import optimizations. Now, I will describe each of these...
Author: Sunil Agarwal Date: 02/04/2008
What are the Bulk Import Optimizations?
Bulk import provides an optimized insert path that minimizes this overhead with following...
Author: Sunil Agarwal Date: 02/04/2008
Why Bulk Import?
Most IT shops using SQL Server need to load/import large amount of data obtained from external...
Author: Sunil Agarwal Date: 02/04/2008
Compression Strategies
In the previous blogs, I had described the data compression in SQL Server 2008 and its implications...
Author: Sunil Agarwal Date: 01/26/2008
Details on page compression (page-dictionary)
In the previous blog, I described column-prefix compression that is done as part of PAGE...
Author: Sunil Agarwal Date: 01/18/2008
Details on PAGE compression (column-prefix)
In the previous blog, I had mentioned that the PAGE compression is used to “minimize the data...
Author: Sunil Agarwal Date: 01/17/2008
Data Compression will be available in CTP-6
Thanks to all who have contacted me for their interest in the data compression...
Author: Sunil Agarwal Date: 11/20/2007
Estimating the space savings with data compression
Like I had indicated in my previous blog, it is recommended that you estimate compression savings on...
Author: Sunil Agarwal Date: 11/12/2007
Types of data compression in SQL Server 2008
SQL Server deploys two strategies to compress the data · First, it stores all fixed length...
Author: Sunil Agarwal Date: 11/12/2007
Why not use compressed disk files or disk volumes?
When we think of compressing the database, one of the first question that pops up is why not used...
Author: Sunil Agarwal Date: 11/11/2007
When is too much success a bad thing?
I was talking to a customer the other day who had an interesting problem: Successful...
Author: Kevin Farlee [MSFT] Date: 10/30/2007
Fuzzy backups and RESTORE DATABASE WITH STOPAT
So what’s a “fuzzy backup” and how does it relate to STOPAT? There has been some...
Author: Kevin Farlee [MSFT] Date: 10/26/2007
Data compression techniques and trade offs
Ok, now that we have sort of agreed...
Author: Sunil Agarwal Date: 09/30/2007
Data Compression: Why Do we need it?
As announced in Tech-Ed 2007, data compression is a new and exciting feature targeted to be...
Author: Sunil Agarwal Date: 09/29/2007
ok - really the last blog post - Mondays, Mystic, and a Museum
My new blog's not active until September 1st but I wanted to blog about something cool - and totally...
Author: Paul Randal - MSFT Date: 08/23/2007
Splits and unions...
Hey folks,This is my last blog post on the SQL Server Storage Engine blog as I've made the decision...
Author: Paul Randal - MSFT Date: 07/30/2007
TechEd session video available...
The session I gave at TechEd this year on 'Secrets of Fast Detection and Recovery from Database...
Author: Paul Randal - MSFT Date: 06/27/2007
What happens to non-clustered indexes when the table structure is changed?
Here’s a topic that’s cropped up several times during Q&As at TechEd this year...
Author: Paul Randal - MSFT Date: 06/07/2007
Database mirroring questions from TechEd: failovers and partner timeouts
This year at TechEd there's been even more interest in database mirroring than last year -...
Author: Paul Randal - MSFT Date: 06/06/2007
Katmai == SQL Server 2008 == available to start playing with!
Very exciting!!! On Monday at TechEd we announced the official name of the next version of SQL...
Author: Paul Randal - MSFT Date: 06/05/2007
SQL Server's 'black-box' flight recorder
So I learned something about SQL Server at TechEd today. In Kimberly and Bob Beauchemin's pre-con,...
Author: Paul Randal - MSFT Date: 06/03/2007