SQL Server Code,Tips and Tricks, Performance Tuning

Monday, March 06, 2006

Returning Grouped Random Results

Let's say you have data and you want to return this random but grouped, what do I mean by that? For example you have the following data
sony 4
sony 6
toshiba 1
toshiba 3
mitsubishi 2
mitsubishi 5

When you rerun the query you want the order to be different but the companies have to be grouped together. So the next result could be something like this

toshiba 1
toshiba 3
sony 4
sony 6
mitsubishi 2
mitsubishi 5

To order a result set randomly every single time is easy you just have to add ORDER BY NEWID() and it will be different every single time

To order randomly and keeping it 'ordered/grouped' by company is a little bit trickier
Below are 2 ways to accomplish that. The first way is with a sub query the second is by using RAND and CHECKSUM
If you run the two queries at the same time and look at the execution plan you will notice that the query cost for the query with the sub query is 66.75% (relative to the batch) and for the query with RAND and CHECKSUM it's only 33.25%

For those of you who don't know how to see the execution plan, this is how you do that
CTRL + K (you can also select Query-->Show Execution Plan from the menu bar) then highlight both queries and press F5. Between Grids and Messages you will see a new tab named Execution Plan, click on that tab and you will see a graphical representation of the execution plan

CREATE TABLE #Testcompanies (
Name VARCHAR(50),
ID INT)

INSERT INTO #Testcompanies
SELECT 'toshiba' ,1
UNION ALL
SELECT 'mitsubishi', 2
UNION ALL
SELECT 'toshiba', 3
UNION ALL
SELECT 'sony', 4
UNION ALL
SELECT 'mitsubishi', 5
UNION ALL
SELECT 'sony', 6

--Query using a sub query and NEWID()
SELECT T.*
FROM #Testcompanies T
JOIN (SELECT DISTINCT TOP 100 PERCENT Name,
NEWID() AS GroupedOrder
FROM #Testcompanies
GROUP BY Name
ORDER BY NEWID()) Z
ON T.Name = Z.Name
ORDER BY Z.GroupedOrder

--Query using RAND()
DECLARE @R FLOAT
SET @R = RAND()

SELECT TOP 100 PERCENT *
FROM #TESTCOMPANIES
ORDER BY RAND(@R * CHECKSUM(NAME))

Conversation With Database Legend Jim Gray

Channel 9 has an interesting video with Turing award winner Jim Gray. From the website: "This episode features Jim Gray. He is a "Technical Fellow" in the Scaleable Servers Research Group (Sky Server, Terra Server) and manager of Microsoft's Bay Area Research Center (BARC). Jim has been called a "giant" in the fields of database and transaction processing computer systems. In 1998, Jim was awarded the ACM’s prestigious A.M. Turing Award.

Before joining Microsoft, Jim worked at Digital Equipment Corp (DEC)., Tandem Computers Inc., IBM Corp. and AT&T and he is the editor of the “Performance Handbook for Database and Transaction Processing Systems,” and co-author of “Transaction Processing: Concepts and Techniques.” In this interview, Jim is joined by former colleague from DEC and partner on the Terra Server project, Researcher, Tom Barclay."

Pro SQL Server 2005 Assemblies

Pro SQL Server 2005 Assemblies provides a detailed and example-driven tutorial on how to build and use .NET assemblies. The authors focus on building assemblies in C#, but also provide the equivalent VB .NET code in the supplied code download.

Assemblies are not a complete replacement for T-SQL stored procedures and triggers; rather, they’re enhancements, to be used at the right place and right time. This book examines the ins and outs of assemblies—when they should and should not be used, what you can do with them, and how you can get the most out of them.

Table Of Contents
CHAPTER 1 Introducing Assemblies
CHAPTER 2 Writing a Simple SQL Assembly
CHAPTER 3 The SQL Server NET Programming Model
CHAPTER 4 CLR Stored Procedures
CHAPTER 5 User-Defined Functions
CHAPTER 6 User-Defined Types
CHAPTER 7 User-Defined Aggregates
CHAPTER 8 CLR Triggers
CHAPTER 9 Error Handling and Debugging Strategies
CHAPTER 10 Security
CHAPTER 11 Integrating Assemblies with Other Technologies
INDEX

Sample Chapter: The SQL Server NET Programming Model

Amazon link here

Sunday, March 05, 2006

SQL Server Cursors Not Always Evil

By know you probably heard a thousand times not to use cursors but to use a set based solution instead. Cursors are bad, almost everything that can be written in a cursor can be rewritten to use a set based approach etc etc etc. Well SQL Server MVP Adam Machanic has a great post on his blog that will show you that a cusrsor sometimes is actually faster than a set based solution. Read the post Running sums, redux
A day later Adam created another entry on his blog, this time using SQLCLR code to rewrite the cursor code and improving the execution time by 25%. You can read that entry here (Running sums yet again: SQLCLR saves the day!)
So as you can see cursors do have a place in SQL Server and are sometimes a better option

Thursday, March 02, 2006

Tuesday, February 28, 2006

Find All tables That Contain A Certain Column

This question was posted today on the tek-tips site and also in the microsoft.public.sqlserver.programming newsgroup
The question was how to find all tables that contain a certain column
For example return all tables that have the column OrderID in the Northwind database
You can get all that information from the INFORMATION_SCHEMA.COLUMNS system view, however that view returns tables as well as views
You have to join with INFORMATION_SCHEMA.TABLES and that view contains a column named TABLE_TYPE that you can use to filter on the type (BASE TABLE or VIEW)
I have only selected a couple of columns from the views, use * to see them all

USE Northwind
GO

SELECT c.TABLE_NAME,
TABLE_TYPE,
COLUMN_NAME,
ORDINAL_POSITION,
IS_NULLABLE,
DATA_TYPE,
NUMERIC_PRECISION
FROM INFORMATION_SCHEMA.COLUMNS c
JOIN INFORMATION_SCHEMA.TABLES t ON c.TABLE_NAME = t.TABLE_NAME
WHERE COLUMN_NAME ='orderid'
ORDER BY TABLE_TYPE ,c.TABLE_NAME

Monday, February 27, 2006

SQL Server Upgrade Your Skills To 2005 Webcasts

Are you planning new database development projects this year? Do you need to increase the scale, performance, security, or continuous availability of your existing systems to meet the demands of the business? Microsoft SQL Server 2005 is here, bringing significant enhancements in performance, availability, and security and the most powerful and flexible set of DBA productivity tools we have ever delivered. Our subject matter experts walk through all of the major features and enhancements built into SQL Server 2005 and demonstrate how you can bring these benefits to your organization. Topics covered include SQL Server 2005 management tools, security enhancements, high availability features, replication, and scalability. Also, tune in weekly through June 2006 as Microsoft MVP and Regional Director Kimberly Tripp and her colleagues present an 11-part series on building robust, recoverable, and reliable SQL Server 2005 systems.

Live Webcasts
TechNet Webcast: SQL Server 2005 for the IT Professional (Part 1 of 11): A Fast-Paced Feature Overview and Series Introduction (Level 200)
Friday, March 10, 2006 9:30 A.M.–11:00 A.M. Pacific Time

This first webcast of the SQL Server 2005 for the IT Professional series presents the new features designed to help improve administration, management, and operations. This webcast provides an overview of new features, how they fit together, and best practices for each. Building a robust, recoverable, and reliable system requires knowledge, best practices, and finding the right tool for the job. Join this series to learn how to build the foundation for success.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 2 of 11): Security (Level 200)
Friday, March 17, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Securing SQL Server system requires a variety of defenses. Microsoft SQL Server 2005 provides numerous mechanisms to reduce the attackable surface area, from features that are configured "off by default" to more complex features that can encrypt data to defend against rogue file copies of the database. Understanding how to deploy the wide selection of development and administrative options securely can be complex. In this second webcast of the SQL Server 2005 for the IT Professional series, learn about best practices for sorting through the options to optimally secure SQL Server 2005. Additionally, this webcast addresses security issues such as protecting and recovering data as it relates to encryption key escrow and recovery.

TechNet Webcast: SQL Server for the IT Professional (Part 3 of 11): Understanding Installation Options and Initial Configuration (Level 200)
Friday, March 24, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Graphical installation requires you to continually click next through the options with the idea that you can always change the settings later. We believe there is a much better way. Make the right decisions at installation to ensure a more secure and properly configured environment. In this third webcast of the SQL Server 2005 for the IT Professional series, we present Service Account options, Authentication Mode, secure sockets layer (SSL) security (without installing SSL), password requirements, and installation directory structures. We explain code page and sort order selection for new and upgraded installations. The session wraps up with the changes necessary immediately after installation: setting the system administrator (SA) password and using the SQL Surface Area Configuration tool and Configuration Manager.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 4 of 11): Upgrade Considerations and Migration Paths (Level 200)
Friday, March 31, 2006 9:30 A.M.–11:00 A.M. Pacific Time

In this fourth webcast of the SQL Server 2005 for the IT Professional series, we help you prepare your migration path to minimize potential failures. In the first half of this session learn how to use the Upgrade Advisor and what to look for in your existing databases. The second half helps you to understand your options and explains the Copy Database Wizard, Detach/Attach, and Backup/Restore features. Join us to create a careful and easy test plan today so that your migration is easy tomorrow!

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 5 of 11): Effective Use of the New Management Tools (Level 200)
Friday, April 7, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Microsoft SQL Server 2005 introduces a new set of tools that are a radical departure from previous versions. If you want to avoid a steep learning curve attend this fifth webcast of the SQL Server 2005 for the IT Professional series, presented by Kimberly Tripp, to discover the new features designed to make the database administration and database development teams more effective and productive. Understanding the impact of the Microsoft Visual Studio shell—and where SQL Server Management Studio (SSMS) diverges from the standard shell—can help you to use SSMS more effectively. The primary focus of this webcast is on solutions, projects, customizing the query tool, and source control integration.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 6 of 11): New Application Design Patterns for Scalability and Availability and the Operational Implications of Service Broker (Level 200)
Friday, April 14, 2006 9:30 A.M.–11:00 A.M. Pacific Time

SQL Service Broker is an integral part of the database in Microsoft SQL Server 2005. Understanding why developers may choose to use this is one part of the picture, but some internal SQL Server features use it as well. In this sixth webcast of the SQL Server 2005 for the IT Professional series, we present what new data objects comprise Service Broker, what new SQL statements you need to know about, and how you manage it, secure it, and monitor it, along with information about when it is appropriate to consider a Broker-based application. Join us to learn about dynamic management views and profiler support, in addition to how you can troubleshoot operational problems. The webcast also explains the internal functions run by Service Broker and how they work.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 7 of 11): Technologies and Features to Improve Availability (Level 200)
Friday, April 21, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Find the right technology for the job in this seventh webcast of the SQL Server 2005 for the IT Professional series. Join us to learn which technologies provide the right solution for a specific problem, as well as the pros and cons of each technology. Designing a system to protect you against the faults most likely to occur is the first and most important strategy, but finding the right combination to minimize both downtime and data loss is critical. This webcast covers all of the “Availability” technologies at a glance: remote mirroring, failover clustering, database mirroring, log hipping, replication, redundant array of independent disks (RAID), partial database availability, piecemeal online restore, database snapshots, snapshot isolation, and online operations.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 8 of 11): Implementing Database Mirroring in SQL Server 2005 (Part 1 of 2) (Level 200)
Friday, April 28, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Database mirroring was released for testing when Microsoft SQL Server 2005 shipped as a product. As we approach the first service pack, get prepared for the release of database mirroring for general production use and understand the barriers of what database mirroring will protect against. Attend this first part in the eighth webcast of the SQL Server 2005 for the IT Professional series to obtain better insight for when database mirroring should be implemented as well as what to expect moving forward in service pack 1 (SP1).

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 9 of 11): Implementing Database Mirroring (Part 2 of 2) (Level 200)
Friday, May 5, 2006 9:30 A.M.–11:00 A.M. Pacific Time

After learning about what database mirroring provides—as well as the changes to expect in service pack 1(SP1)—attend this second part in the ninth webcast of the SQL Server 2005 for the IT Professional series to walk through the entire process of implementation, failover, and monitoring. Join us for this slide-free session; it’s all about the demos.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 10 of 11): Recovering from Human Error (Level 200)
Friday, May 12, 2006 9:30 A.M.–11:00 A.M. Pacific Time

Microsoft SQL Server 2005 provides a variety of new features to help deal with the possibility of human error with preventative techniques, investigative techniques, and recovery techniques. Join this tenth webcast of the SQL Server 2005 for the IT Professional series as we look at data definition language (DDL) triggers, event notifications, partial database availability, partial database restores, and database snapshots.

TechNet Webcast: SQL Server 2005 for the IT Professional (Part 11 of 11): Best Practices in Building Robust, Recoverable, and Reliable Systems (Level 200)
Friday, May 19, 2006 9:30 A.M.–11:00 A.M. Pacific Time

In this eleventh and last webcast of the SQL Server 2005 for the IT Professional series, Kimberly Tripp reviews key areas discussed throughout the series to ensure that all areas have been covered. This summary session should keep you thinking, give you more resources to review and use, and point to a few new areas to consider. Building a robust, recoverable, and reliable system takes a myriad of options. Join us to learn what the options are and how you can start making the most of them.

Thursday, February 23, 2006

Three Way To List All Databases On Your Server

Sometimes you want to print out a document with all the databases that exists on one server so that you can compare this against another server for example
Listed below are three ways to accomplish this by using a system table, a system view and an undocumented stored procedure

First Way
Use the INFORMATION_SCHEMA.SCHEMATA system view

SELECT CATALOG_NAME FROM INFORMATION_SCHEMA.SCHEMATA
WHERE CATALOG_NAME NOT IN('master','msdb','tempdb','model')
ORDER BY CATALOG_NAME

Second Way
Use the sysdatabases system table in the master database

SELECT name FROM master..sysdatabases
WHERE name NOT IN('master','msdb','tempdb','model')
ORDER BY Name

Third way
Use the undocumented sp_MSForEachDB procedure

CREATE TABLE #AllDB (Name VARCHAR(100))
INSERT INTO #AllDB
EXEC sp_MSForEachDB 'IF ''?'' NOT IN (''master'', ''model'', ''msdb'', ''tempdb'')
SELECT ''?'' '
SELECT * FROM #AllDB

Tuesday, February 21, 2006

Convert Float Stored As Varchar To Numeric

An interesting problem came up today in the microsoft SQL Server DTS newsgroup
A person tried to convert a varchar value to numeric and got the following message "Error converting data type varchar to numeric."
The problem is that the value stored as varchar is a float and then SQL Server is not able to convert this to a numeric datatype
So first you have to convert to float and then to numeric

DECLARE @Value VARCHAR(50)
SELECT @Value = '5.9499999999999997E-2'

--Error converting data type varchar to numeric.
SELECT CONVERT(NUMERIC(21,20),@Value)

--This works after converting to float first
SELECT CONVERT(NUMERIC(21,20),CONVERT(FLOAT,@Value))

--No problems here since the value in the varchar field can be converted to numeric
DECLARE @Value2 VARCHAR(50)
SELECT @Value2 = '5.9499999999999997'

SQL Server And Business Intelligence Podcast

Channel 9 on MSDN has added another SQL server podcast yesterday, this one is about SQL Server And Business Intelligence
From their page: "Business Intelligence… some people think that is an oxymoron but my friend it is most certainly better than business ignorance which unfortunately is how many business operate. In the last few years most companies have been amassing data at a phenomenal rate but what does that data tell you? Well listen up because my guest today Andrew Brust is going tell you how you can use the tools in SQL Server 2005 to make sense of this treasure trove of competitive information because business intelligence is always better than business stupidity."

The podcast is 32 minutes and 58 seconds and you can get it here

Enjoy the show

Monday, February 20, 2006

XML In SQL Server 2005 Podcast

XML in SQL Server 2005
Channel9 at MSDN.com has a great SQL Server 2005 and XML podcast
From the page: "How much code have you seen that is devoted to simply shredding XML and storing it in a database? What if you didn't need to do that anymore? What if you could store XML in all of it's unstructured hierarchical goodness and just leave it at that? Well my friend, you are in luck because on this episode Shankar Pal of the SQL Server team is going to tell you all about the details of the great new XML support in SQL Server 2005."

Get the podcast here

Enjoy the show

Friday, February 17, 2006

Sort A SQL Server Table With CASE Or CHARINDEX

Let's say you have a table with states in your database, you only have 3 values NY, ME and SC.
You want to order the result like this: first NY followed by SC and ME last.
You can do that in two different ways
One: use a case statement in your order by
Two: use Charindex in your order by
Let's see how that works

CREATE TABLE #TEST (
STATE CHAR(2))

INSERT INTO #TEST
SELECT 'ME' UNION ALL
SELECT 'ME' UNION ALL
SELECT 'ME' UNION ALL
SELECT 'SC' UNION ALL
SELECT 'NY' UNION ALL
SELECT 'SC' UNION ALL
SELECT 'NY' UNION ALL
SELECT 'SC'

-- order by using CASE

SELECT *
FROM #TEST
ORDER BY CASE STATE
WHEN 'NY' THEN 1
WHEN 'SC' THEN 2
ELSE 3
END

--Order by using CHARINDEX
SELECT *
FROM #TEST
ORDER BY CHARINDEX(STATE,'NY-SC-ME')

--or without NY since CHARINDEX will return 0 for NY and it will be first
SELECT *
FROM #TEST
ORDER BY CHARINDEX(STATE,'SC-ME')

--the problem is of course if you have more values and you only want to have NY and SC showing up first and second
--let's insert 2 more rows
INSERT INTO #TEST
SELECT 'IL'
UNION ALL
SELECT 'CA'

-- Now the CHARINDEX Order doesn't work
-- the trick is to make it Descending and switch the states around
SELECT *
FROM #TEST
ORDER BY CHARINDEX(STATE,'SC-NY') DESC

or this way

--Order by using CHARINDEX DESC
SELECT *
FROM #TEST
ORDER BY CHARINDEX(STATE,'ME-SC-NY') DESC

Tuesday, February 14, 2006

User Definded Functions And GETDATE() (nondeterministic built-in functions )

I have read on Louis Davidson's blog a post about UDF and being able to use GETDATE() in a UDF in SQL server 2005. I wasn't aware of that so I would like to bring it to your attention
In SQL server 2005 you are able to use the following nondeterministic built-in functions in Transact-SQL user-defined functions:
CURRENT_TIMESTAMP
GET_TRANSMISSION_STATUS
GETDATE
GETUTCDATE
@@PACK_SENT
@@PACK_RECEIVED
@@MAX_CONNECTIONS
@@PACKET_ERRORS
@@CONNECTIONS
@@TIMETICKS
@@CPU_BUSY
@@TOTAL_ERRORS
@@DBTS
@@TOTAL_READ
@@IDLE
@@TOTAL_WRITE
@@IO_BUSY

So let's get started and test it out, I will create 2 UDF's one that uses GETDATE() and one that uses DATEADD() and GETDATE()

CREATE FUNCTION fnNonDeterministic ()
RETURNS DATETIME
AS
BEGIN
RETURN GETDATE()
END
GO

CREATE FUNCTION fnNonDeterministicAdd (@Days int)
RETURNS DATETIME
AS
BEGIN
RETURN DATEADD(d,@Days,GETDATE())
END
GO

--Let's see what the ouput is
SELECT dbo.fnNonDeterministic() AS DateReturned,
dbo.fnNonDeterministicAdd(2) AS DateAddReturned

Monday, February 13, 2006

Use CHARINDEX, LEN and SUBSTRING To Find Data Between Characters

Let's say you get data in the following format aaaa/bbbb/cccc/dddd/eeee
What you need from this file is just the data between the first and the last forward slash (in thid case bbbb)
If there is no slash in the file then grab all the data, if there is only 1 slash then grab everything after that slash
This was actually one of the questions that I have answered on tek-tips so yes data like this does exist.
How do you attack such a problem?
First you have to find the first slash, you do that by using CHARINDEX, CHARINDEX will return the position where the first slash is located, then you use CHARINDEX again with SUBSTRING to find the Second slash, finally you use SUBSTRING with the LEFT function and the difference between the 2 CHARINDEX calls as the length
I used a replace function at the beginning to check if there is more than 1 slash or not and then a case statement later on depending on the outcome of that replace function
Let’s see how I did it

--Create some test data
CREATE TABLE #test (ValueField VARCHAR(50))
INSERT INTO #test
SELECT ' /aaaa' UNION ALL
SELECT ' /yyyy/bbbb ' UNION ALL
SELECT 'zzzzz/c/defgh ' UNION ALL
SELECT 'VVVVV'

--This is our delimiter
DECLARE @Delimiter CHAR(1)
SET @Delimiter = '/'

--Show the whole field and the extracted value
SELECT ValueField AS Originalvalue,
CASE WHEN LEN(ValueField) -LEN(REPLACE(ValueField,@Delimiter,'')) > 1
THEN LEFT(SUBSTRING(ValueField,CHARINDEX(@Delimiter,ValueField)+1 ,LEN(ValueField)),CHARINDEX(@Delimiter,SUBSTRING(ValueField,CHARINDEX(@Delimiter,ValueField)+1 ,LEN(ValueField)))-1)
ELSE SUBSTRING(ValueField,CHARINDEX(@Delimiter,ValueField)+1 ,LEN(ValueField))END AS ExtractedValue
FROM #test

Friday, February 10, 2006

How To Check For A Certain Time With SQL

Sometimes you have jobs and you don't know how long they will run
Let's just assume here that the job has 2 steps
You run step 1 and it takes x hours, you only want to run step 2 if it's before 5:45 AM because some other job will start at 6:00 AM and you don't want those 2 jobs hitting the same table at the same time (a real world scenario might be different of course, this is just a simplified version)

I hardcoded 05:45:00.000 here, you can of course store this in a parameter or even in a table so that you only have to change it in one place

--Get today's date
DECLARE @CurrentDateTime DATETIME
SET @CurrentDateTime = GETDATE()

-- create a 2nd parameter and append the time that you need to check for
DECLARE @TimeToChek DATETIME
SELECT @TimeToChek = CONVERT(VARCHAR,@CurrentDateTime,101) + ' 05:45:00.000'

IF (@CurrentDateTime <= @TimeToChek)
-- It is before 5:45 AM
BEGIN
SELECT 'before 5:45am' OutputStatus,
@CurrentDateTime AS CurrentTime,
@TimeToChek AS TimeToCheck
END
ELSE
-- it is before 5:45 AM
BEGIN
SELECT 'Not before 5:45am' OutputStatus,
@CurrentDateTime AS CurrentTime,
@TimeToChek AS TimeToCheck
END

Thursday, February 09, 2006

Beginning SQL Server 2005 For Developers: From Novice To Professional

Apress has published their latest SQl server 2005 book: Beginning SQL Server 2005 For Developers: From Novice To Professional

SQL Server 2005 will increase your programming options, productivity, analysis, and database management. If you have some basic knowledge of relational databases and want to start a career as a developer using SQL Server, then this book is your ideal first step. It explains the core jobs and roles for developing a database in both SQL Server 2000 and 2005.

This book features practical steps to help you overcome issues you’re likely to encounter. You’ll learn to use SQL for querying, inserting, updating, and deleting data. You’ll also learn how to back up and restore databases for basic administration in SQL Server. Further, you’ll cover how to build a complete database, from the fundamentals of relational database design to table and index creation.

Additionally, you’ll start to program in T-SQL, SQL Server’s implementation (and extension) of the SQL programming language, and you’ll come away with effective programming techniques using stored procedures and triggers. The book also includes a CD that contains an evaluation edition of SQL Server 2005 so you can start building database applications right away.

This book is 536 pages and below is the table of contents

CHAPTER 1 SQL Server 2005 Overview and Installation
CHAPTER 2 SQL Server Management Studio
CHAPTER 3 Database Design and Creation
CHAPTER 4 Security
CHAPTER 5 Defining Tables
CHAPTER 6 Creating Indexes and Database Diagramming
CHAPTER 7 Database Backups, Recovery, and Maintenance
CHAPTER 8 Working with the Data
CHAPTER 9 Building a View
CHAPTER 10 Stored Procedures
CHAPTER 11 T-SQL Essentials
CHAPTER 12 Advanced T-SQL
CHAPTER 13 Triggers
CHAPTER 14 SQL Server 2005 Reporting Services
APPENDIX Glossary of Terms
INDEX

Download chapter 4 (security) here

If you want to puchase this book the Amazon link is here

Check If Temporary Table Exists

How do you check if a temp table exists?
You can use IF OBJECT_ID('tempdb..#temp') IS NOT NULL
Let's see how it works

--Create table
USE Norhtwind
GO

CREATE TABLE #temp(id INT)

--Check if it exists
IF OBJECT_ID('tempdb..#temp') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

--Another way to check with an undocumented optional second parameter
IF OBJECT_ID('tempdb..#temp','u') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

--Don't do this because this checks the local DB and will return does not exist
IF OBJECT_ID('tempdb..#temp','local') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

--unless you do something like this
USE tempdb
GO

--Now it exists again
IF OBJECT_ID('tempdb..#temp','local') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

--let's go back to Norhtwind again
USE Norhtwind
GO

--Check if it exists
IF OBJECT_ID('tempdb..#temp') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

now open a new window from Query Analyzer (CTRL + N) and run this code again
--Check if it exists
IF OBJECT_ID('tempdb..#temp') IS NOT NULL
BEGIN
PRINT '#temp exists!'
END
ELSE
BEGIN
PRINT '#temp does not exist!'
END

It doesn't exist and that is correct since it's a local temp table not a global temp table

Well let's test that statement
--create a global temp table
CREATE TABLE ##temp(id INT) --Notice the 2 pound signs, that's how you create a global variable

--Check if it exists
IF OBJECT_ID('tempdb..##temp') IS NOT NULL
BEGIN
PRINT '##temp exists!'
END
ELSE
BEGIN
PRINT '##temp does not exist!'
END

It exists, right?
Now run the same code in a new Query Analyzer window (CTRL + N)

--Check if it exists
IF OBJECT_ID('tempdb..##temp') IS NOT NULL
BEGIN
PRINT '##temp exists!'
END
ELSE
BEGIN
PRINT '##temp does not exist!'
END

And yes this time it does exist since it's a global table

Wednesday, February 08, 2006

SQL:Format Data From Numberformat To Timeformat

Sometimes you have data that's in a number format and you need to show it in a time format. Instead of 2.25 you need to show 02:15
In that case you can use a combination of CONVERT and DATEADD
Run the examples below to see how it works

DECLARE @a DECIMAL(6,2)
SELECT @a = 3.00
SELECT @a AS OldValue,
CONVERT(CHAR(5), DATEADD(ss, @a * 3600, 0), 108) AS TimeFormatted

SELECT @a = 3.15
SELECT @a AS OldValue,
CONVERT(CHAR(5), DATEADD(ss, @a * 3600, 0), 108) AS TimeFormatted

SELECT @a = 3.25
SELECT @a AS OldValue,
CONVERT(CHAR(5), DATEADD(ss, @a * 3600, 0), 108) AS TimeFormatted

SELECT @a = 3.75
SELECT @a AS OldValue,
CONVERT(CHAR(5), DATEADD(ss, @a * 3600, 0), 108) AS TimeFormatted

Friday, February 03, 2006

SQL Server Related Webcasts For February 2006

Microsoft has scheduled 18 new new webcasts for February, covering such topics as SQL Server 2005 Essentials: SQL/CLR, Reporting Services Basics, Using .NET Procedural Code in SQL Server 2005m Using Analysis Services, Introduction to Data Mining and more. The whole list with their start dates is listed below. Enjoy

MSDN Webcast: SQL Server 2005 Essentials: SQL/CLR (Part 1 of 14) (Level 200)
Friday, February 03, 200610:00 AM Pacific Time As the first of a 14-part series, this webcast covers what it means to be a Microsoft .NET runtime host. Topics include how Microsoft SQL Server 2005 works with the .NET 2.0 application programming interfaces (APIs) to make loading and running code safe, reliable, and scalable.

MSDN Webcast: SQL Master Class: Reporting Services Basics (Level 200)
Tuesday, February 07, 20069:00 AM Pacific Time Microsoft SQL Server Reporting Services was released in 2004 to provide developers with an easy way to extract and share information captured in a relational database. In this webcast, we explore how to create basic reports, link them to together, and provide end users with a way to get the information they need.

MSDN Architecture Webcast: Build Reliable Application Platforms with SQL Server 2005 (Level 200)
Tuesday, February 07, 20061:00 PM Pacific Time Join us to discover the many advantages of using SQL Server 2005 for application building.

MSDN Webcast: SQL Server 2005 Essentials: Using .NET Procedural Code in SQL Server 2005 (Part 2 of 14) (Level 200)
Friday, February 10, 200610:00 AM Pacific TimeThis second webcast of a 14-part series covers in detail how to write procedures, functions, and triggers using a managed language. Additionally, we discuss when to use managed code and when to use Transact-SQL.

TechNet Webcast: Introduction to SQL Server 2005 Reporting Services (Level 200)
Monday, February 13, 20069:30 AM Pacific TimeAttend this webcast to learn about the new capabilities in SQL Server 2005 Reporting Services.

TechNet Webcast: Introduction to SQL Server 2005 Analysis Services (Level 200)
Tuesday, February 14, 20069:30 AM Pacific Time This webcast shows how you can use SQL Server Analysis Services to build a highly scalable business intelligence infrastructure that supports the analytics your business needs to improve overall performance.

TechNet Webcast: Introduction to Data Mining with SQL Server 2005 (Level 200)
Thursday, February 16, 20069:30 AM Pacific TimeThis webcast introduces you to the possibilities of data mining and predictive analytics.

MSDN Webcast: SQL Server 2005 Essentials: The SqlServer Data Provider (Part 3 of 14) (Level 200)
Friday, February 17, 200610:00 AM Pacific TimeThis third webcast of a 14-part series covers the new provider, System.Data.SqlServer, and discusses how connections, variable mappings, and other functions built into Transact-SQL are handled when a Microsoft .NET language is used.

TechNet Webcast: Advanced SQL Server 2005 Reporting Services (Level 300)
Monday, February 20, 20069:30 AM Pacific Time Topics in this webcast include: how to use the built-in expression language, report parameterization (data driven, multi-valued, and hierarchical), supporting multiple data sources (including relational, multi-dimensional, and XML), and making reports interactive.

TechNet Webcast: Security in SQL Server 2005 (Level 200)
Monday, February 20, 200611:00 AM Pacific TimeThis webcast highlights security concepts that are new to Microsoft SQL Server 2005, such as encryption and user-schema separation, and looks at how SQL Server 2005 breaks security down into several distinct areas.

MSDN Webcast: Using ADO.NET with Your Lotus Notes Applications (Level 400)
Tuesday, February 21, 20068:00 AM Pacific TimeADO.NET is the standard method for Microsoft Visual Studio .NET applications to interact with data sources such as Microsoft SQL Server, the IBM DB2 Universal Database, and Oracle.

TechNet Webcast: A Technical Overview of High Availability Features in SQL Server 2005 (Level 200)
Friday, February 24, 20068:00 AM Pacific TimeThere are many barriers to achieving high availability in a database system, and only some of them can be addressed by database management systems technology. This webcast examines some of the features of Microsoft SQL Server 2005—the latest release of the SQL Server product—that can help you overcome some of these barriers.

MSDN Webcast: SQL Server 2005 Essentials (Part 4 of 14): User-Defined Types and User-Defined Aggregates (Level 200)
Friday, February 24, 200610:00 AM Pacific TimeIn this fourth module of the 14-part series, learn about using .NET objects and how you can use them inside the database.

TechNet Webcast: Introduction to SQL Server 2005 Report Builder (Level 200)
Monday, February 27, 20069:30 AM Pacific Time Learn how Microsoft SQL Server 2005 Reporting Services is meeting the demand for end-user, ad hoc reporting.

TechNet Webcast: Introduction to SQL Server 2005 Integration Services (Level 200)
Monday, February 27, 200611:30 AM Pacific Time In this webcast, we introduce you to the enterprise-class capabilities of Integration Services including dedicated management functionality, collaborative development environment, and high scalability and reliability. You also learn how you can take advantage of SQL Server 2005 Integration Services to implement data quality, data profiling, and custom transforms in your organization.

MSDN Webcast: SQL Master Class: Using Report Builder (Level 200)
Tuesday, February 28, 20069:00 AM Pacific Time Find out about the new Report Builder in Microsoft SQL Server 2005 that allows end users to customize reports to their liking.

TechNet Webcast: Advanced SQL Server 2005 Integration Services (Level 300)
Tuesday, February 28, 200611:30 AM Pacific Time This webcast presents the key architectural enhancements in SSIS that makes it extremely scalable.

Thursday, February 02, 2006

Varchar To Varbinary And Vice Versa

I have received an email from someone in Taiwan who looked at the contact me blog entry and wanted to know how I ‘encrypted’ my email address like that. Well there really is not much to it, you just convert the email string to varbinary. Then you convert it back to varchar to get the string back
For example if my email address is abc@qwerty.NotCom then you would do
SELECT CONVERT(VARBINARY(17),'abc@qwerty.NotCom')

This would return 0x616263407177657274792E4E6F74436F6D

Then you do
SELECT CONVERT(VARCHAR(17),0x616263407177657274792E4E6F74436F6D)
to see the string again
Of course you will have to increase the size of the varchar and the varbinary field if it exceeds 17 bytes

SQL Server Site Geo Map For January 2006

These are the countries where the bulk of the visitors for this blog are coming from. As you can see most of the visitors are from the US and Europe, Asia is in third place. When I look at the maps day by day I also see some visitors from Africa and the Middle East but you need more than one visitor per city in order for it to show up in the monthly map.

Wednesday, February 01, 2006

Login failed for user 'sa'. Reason: Not associated with a trusted SQL Server connection. SQL 2005

I am seeing a lot of searches on this blog or reaching this blog from MSN/Google with this search “SQL 2005 Login failed for user 'sa'. Reason: Not associated with a trusted SQL Server connection.” So this is what causes the problem: your SQL Server has been setup with windows authentication only. In order to make it mixed mode authentication right click on the server name in enterprise manager select properties and click on the security tab. Select SQL server and Windows Authentication mode(see picture…) and that will fix it The cool thing about SQL server 2005 is that you can script this out so that you can run the code on multiple servers instead of going to all the servers and clicking etc. Just click on script and code like the one below will be generated

USE [master]
GO
EXEC xp_instance_regwrite N'HKEY_LOCAL_MACHINE', N'Software\Microsoft\MSSQLServer\MSSQLServer', N'LoginMode', REG_DWORD, 2
GO

For the SQL server 2000 version go here

Monday, January 30, 2006

NULL Trouble In SQL Server Land

I am seeing a lot of searches for SQL + Nulls from this site so I decided to blog about it
Before I start I would like to point out that all the code will behave this way if ANSI_NULLS is set to on ,not to off

CREATE TABLE testnulls (ID INT)
INSERT INTO testnulls VALUES (1)
INSERT INTO testnulls VALUES (2)
INSERT INTO testnulls VALUES (null)

CREATE TABLE testjoin (ID INT)
INSERT INTO testjoin VALUES (1)
INSERT INTO testjoin VALUES (3)

--We get back value 1 here
SELECT * FROM testjoin WHERE ID IN(SELECT ID FROM testnulls)

--Nothing is returned
SELECT * FROM testjoin WHERE ID NOT IN(SELECT ID FROM testnulls)

--Value 3 is returned
SELECT * FROM testjoin WHERE ID NOT IN(SELECT ID FROM testnulls WHERE ID IS NOT NULL)

--value 3 is returned
SELECT * FROM testjoin j
WHERE NOT EXISTS (SELECT n.ID
FROM testnulls n
WHERE n.ID = j.ID)

--value 3 is returned
SELECT j.* FROM testjoin j
LEFT OUTER JOIN testnulls n ON n.ID = j.ID
WHERE n.ID IS NULL

--a count of 3 is returned
SELECT COUNT(*) FROM testnulls

-- a count of 2 is returned, the count ignores NULL values
SELECT COUNT(id) FROM testnulls

--By using coalesce the count is also 3
SELECT COUNT(COALESCE(id,0)) FROM testnulls

--all 3 rows are returned
SELECT * FROM testnulls

-- 1 row is returned
SELECT * FROM testnulls
WHERE ID = 1

-- only 1 row is returned the row with the NULL value is ignored
SELECT * FROM testnulls
WHERE ID <> 1

-- Now both rows that are not 1 are returned
SELECT * FROM testnulls
WHERE ID <>1
OR ID IS NULL

-- Now both rows that are not 1 are returned also
SELECT * FROM testnulls
WHERE COALESCE(ID,0) <> 1

Some more NULL Fun
You can''t compare NULL with anything
Since both values are unknown even a comparison with another NULL is unknown

DECLARE @v INT
DECLARE @v2 INT

SELECT @v =NULL,@v2 = NULL
IF @v = @v2
SELECT 'yes'
ELSE
SELECT 'No'

Be carefull with forgetting to initialize parameters while building string

DECLARE @SQL VARCHAR(500)
DECLARE @Id INT

SELECT @SQL = 'SELECT * FROM testnulls
WHERE ID =' + CONVERT(VARCHAR,@Id)

SELECT @SQL

Professional SQL Server 2005 Integration Services

Professional SQL Server 2005 Integration Services has just been published by WROX, a co-worker already ordered it and I skimmed though it during lunch and ordered my own copy. I already own SQL server 2000 DTS and was very satisfied with that book. I have included 2 links to 2 sample chapters as well as a link to Amazon, so far there are 2 reviews on Amazon and both are 5 stars. The book itself is 720 pages and below is the table of contents

Foreword.
Preface.
Acknowledegements.
Author Bios.
Introduction.

1. Services.
2. Importing and Exporting Data.
3. SSIS Fundamentals.
4. Data Flow Elements and Transforms.
5. Creating Your First Package.
6. Advanced Tasks and Transforms.
7. Scripting in DTS.
8. Accessing Heterogenous Data.
9. Reliability and Scalability.
10. Understanding the Integration Services Engine.
11. Applying the Integration Services Engine.
12. DTS 2000 Migration and Metadata Management.
13. Error and Event Handling.
14. Programming and Extending SSIS.
15. Adding a User Interface to Components.
16. External Management and WMI.
17. Using SSIS with External Applications.
18. SSIS Software Development Life Cycle.
19. Case Study: Typical Relational ETL.
Index.

Chapter 1 Welcome to SQL Server Integration Services sample chapter is available here
Chapter 5 Creating an End-to-End Package is available from Brian Knight's blog

The Amazon link is here

Friday, January 27, 2006

Format SQL Server Decimal Data

Yesterday someone posted a question in the SQL server
microsoft.public.sqlserver.programming news group about formatting decimal data. The person did not want trailing zeros or a decimal point if the amount was whole
The trick to do this is convert the decimal point to a space, rtrim it and then convert the space to a decimal. When you do that the trailing decimal point will vanish. The same applies for trailing zeros of course

output
.25000
.50000
1.00000
1.50000
2.00000
3.00000

desired output
0.25
0.5
1
1.5
2
3

--first create our test data table
CREATE TABLE #testdecimals(testdata DECIMAL(20,5))
INSERT INTO #testdecimals
SELECT 0.2500 UNION ALL
SELECT 0.5000 UNION ALL
SELECT 1.0000 UNION ALL
SELECT 1.5000 UNION ALL
SELECT 2.0000 UNION ALL
SELECT 3.0000

-- regular select
SELECT testdata
FROM #testdecimals

--formatted select
SELECT REPLACE(RTRIM(REPLACE(REPLACE(RTRIM(REPLACE(CONVERT(varchar,testdata),'0',' ')),' ','0'),'.',' ')),' ','.')
FROM #testdecimals

Use XP_CMDSHELL To Get All File Names With Size In A Directory

To get all the files with their filesize in a directory use xp_cmdshell with a temporary table
After the temporary table is populated you will be able to sort the result set any way you like

CREATE TABLE #tempList (Files VARCHAR(500))

INSERT INTO #tempList
EXEC MASTER..XP_CMDSHELL 'dir c:\ '

--delete all directories
DELETE #tempList WHERE Files LIKE '%<dir>%'

--delete all informational messages
DELETE #tempList WHERE Files LIKE ' %'

--delete the null values
DELETE #tempList WHERE Files IS NULL

--get rid of dateinfo
UPDATE #tempList SET files =RIGHT(files,(LEN(files)-20))

--get rid of leading spaces
UPDATE #tempList SET files =LTRIM(files)

--split data into size and filename
SELECT LEFT(files,PATINDEX('% %',files)) AS Size,
RIGHT(files,LEN(files) -PATINDEX('% %',files)) AS FileName
FROM #tempList

Wednesday, January 25, 2006

Login failed for user 'sa'. Reason: Not associated with a trusted SQL Server connection. SQL 2000

I am seeing a ton of searches on this blog or reaching this blog from MSN/Google with this search “Login failed for user 'sa'. Reason: Not associated with a trusted SQL Server connection.” So this is what causes the problem: your SQL Server has been setup with windows authentication only. In order to make it mixed mode authentication right click on the server name in enterprise manager select properties and click on the security tab. Select SQL server and Windows (see picture…) and that will fix it
I will monitor the searches and write more stuff about things that people are searching for.
For the SQL server 2005 version go here

Tuesday, January 24, 2006

Kill All Connections To Your SQL Server Database

Sometimes you need to restore a database and put it in single user mode but you can't because people are still using it. I will show you 2 ways to accomplish that
The first way is to loop through the sysprocesses table and kill all the processes one by one. The second way is to do an alter statement on the DB

--loop through the sysprocesses
DECLARE @sysDbName SYSNAME
SELECT @sysDbName = 'northwind'

SELECT IDENTITY(int, 1,1)AS ID,spid
INTO #LoopProcess
FROM master..sysprocesses
WHERE dbid = DB_ID(@sysDbName)

DECLARE @SPID SMALLINT
DECLARE @SQL VARCHAR(255)
DECLARE @MaxID INT, @LoopID INT

SELECT @LoopID =1,@MaxID = MAX(ID) FROM #LoopProcess

WHILE @LoopID <= @MaxID
BEGIN
SELECT @SPID = spid FROM #LoopProcess WHERE ID = @LoopID
SELECT @SQL = 'KILL ' + CONVERT(VARCHAR, @SPID)

EXEC( @SQL )

SELECT @LoopID = @LoopID +1
END

DROP TABLE #LoopProcess

--alter the DB by making it single user (all transaction will be rolled back)
ALTER DATABASE northwind SET SINGLE_USER WITH ROLLBACK IMMEDIATE

--do your restore here

-- Make the DB multi user again
ALTER DATABASE northwind SET MULTI_USER

Sunday, January 22, 2006

Improve Your SQL Server Skills By Helping Others

Participating in forums and newsgroups is a great way to improve your SQL Server skills. You will see other people's problems and if you are just starting out then just relax and read the responses. The responses are most likely from a SQL Server MVP and these are top-quality. You will see many familiar authors in the MS public newsgroups such as Kalen Delaney, Itzik Ben-Gan, Adam Machanic, Louis Davidson and more. I have encountered SQL Server problems and remembered that I read about this on a SQL Server newsgroup and that a person posted a solution, from then on it's quick Google search and there you have it.

MS Public SQL Server Newsgroups
microsoft.public.sqlserver.newusers
microsoft.public.sqlserver.programming
microsoft.public.sqlserver.server

And a full list here

BTW these newsgroups can also be accessed by a newsreader as NTTP

Besides the newsgroups I also participate in the SQL Server Tek-Tip Forums for programming and administration What's great about Tek-Tips is the fact that people give stars to people who post a useful solution. So this will give you more incentives to post a good solution. You can also write searchable FAQ's

Tek-Tip SQL Server Forums
programming
administration

Like I said before you don't have to post solution but do at least spend some of your time reading the solutions to people's problems because sooner or later you might encounter them yourself.

Thursday, January 19, 2006

sp_MSforeachtable

Find out fragmentation levels for all tables in your database by running the undocumented stored procedure sp_MSforeachtable

-- Create temp table
CREATE TABLE #fraglist (
ObjectName CHAR (255),
ObjectId INT,
IndexName CHAR (255),
IndexId INT,
Lvl INT,
CountPages INT,
CountRows INT,
MinRecSize INT,
MaxRecSize INT,
AvgRecSize INT,
ForRecCount INT,
Extents INT,
ExtentSwitches INT,
AvgFreeBytes INT,
AvgPageDensity INT,
ScanDensity DECIMAL,
BestCount INT,
ActualCount INT,
LogicalFrag DECIMAL,
ExtentFrag DECIMAL)

--Insert fragmentation level information
sp_MSforeachtable 'insert into #fraglist exec(''DBCC showcontig (''''?'''') with tableresults '') '

--Get all the info back
SELECT * FROM #fraglist

After you have run this you can determine which tables should be defragmented by looking at the AvgFreeBytes, ScanDensity, LogicalFrag and ExtenFrag columns

Monday, January 16, 2006

Find All Tables Without Triggers In SQL Server

Sometimes you want to change tables by adding columns, dropping or changing column types
You want to make sure that there aren't any tables that have triggers on them so that stuff doesn't start to break after you make these changes
I present two ways to accomplish that, the first way is by joining the INFORMATION_SCHEMA.TABLES view with the sysobjects system table.
The second way is to do a self join on the sysobjects system table. Both of these queries will return the same result

SELECT t.TABLE_NAME FROM INFORMATION_SCHEMA.TABLES t
LEFT JOIN(SELECT OBJECT_NAME(o.parent_obj) AS TableName
FROM sysobjects o
WHERE OBJECTPROPERTY(o.[id], 'IsTrigger') = 1
) tr ON t.TABLE_NAME= tr.TableName
WHERE tr.TableName IS NULL
AND TABLE_TYPE ='BASE TABLE'
ORDER BY t.TABLE_NAME

SELECT s1.name FROM sysobjects s1 LEFT JOIN sysobjects s2 ON
s1.id =s2.parent_obj
AND s2.xtype = 'TR'
WHERE s2.name IS NULL
AND s1.xtype = 'U'
ORDER BY s1.name

Monday, January 09, 2006

ISNUMERIC SQL Server Trouble

If you use the ISNUMERIC function to determine if a value is numeric you might be in for a surprise
Run the 3 lines of code below and you will see what I mean

DECLARE @S VARCHAR(50)
SET @S = CHAR(9) --- @S NOW CONTAINS THE TAB CHARACTER
SELECT ISNUMERIC(@S), ISNUMERIC(CHAR(9)),ISNUMERIC('1D2'),ISNUMERIC('D')

As you can see TAB is returned as numeric as well the value 1D2
A better way to test for this would be with LIKE and %[a-z]%
If you run the example below you will see that the select statement with the ISNUMERIC function or LIKE returns one row more than the statement with LIKE and ISNUMERIC combined

CREATE TABLE #foo (Value VARCHAR(20))
INSERT INTO #foo
SELECT '1' UNION ALL
SELECT '3' UNION ALL
SELECT 'B' UNION ALL
SELECT '2' UNION ALL
SELECT '33.331' UNION ALL
SELECT 'adad1' UNION ALL
SELECT '1d2' UNION ALL
SELECT '^' UNION ALL
SELECT '17777.999'

--returns ^
SELECT * FROM #foo
WHERE Value NOT LIKE '%[a-z]%'

--returns 1d2
SELECT * FROM #foo
WHERE ISNUMERIC(Value) = 1

--returns correct result
SELECT * FROM #foo
WHERE Value NOT LIKE '%[a-z]%'
AND ISNUMERIC(Value) = 1

Friday, January 06, 2006

Compare Tables With Tablediff

In SQL Server 2005 there is a new utility to compare the data in two tables these can be in different tables and different servers.
The utility is Tablediff

The location is Program Files\Microsoft SQL Server\90\COM\tablediff.exe

From BOL:

The tablediff utility is used to compare the data in two tables for non-convergence, and is particularly useful for troubleshooting non-convergence in a replication topology. This utility can be used from the command prompt or in a batch file to perform the following tasks:

A row by row comparison between a source table in an instance of Microsoft SQL Server acting as a replication Publisher and the destination table at one or more instances of SQL Server acting as replication Subscribers.

Perform a fast comparison by only comparing row counts and schema.

Perform column-level comparisons.

Generate a Transact-SQL script to fix discrepancies at the destination server to bring the source and destination tables into convergence.

Log results to an output file or into a table in the destination database.

Look it up in Books On Line

Tuesday, January 03, 2006

Troubleshooting Performance Problems in SQL Server 2005

It is not uncommon to experience the occasional slow down of a SQL Server database. A poorly designed database or a system that is improperly configured for the workload are but several of many possible causes of this type of performance problem. Administrators need to proactively prevent or minimize problems and, when they occur, diagnose the cause and take corrective actions to fix the problem. This article provides step-by-step guidelines for diagnosing and troubleshooting common performance problems by using publicly available tools such as SQL Server Profiler, System Monitor, and the new Dynamic Management Views in SQL Server 2005
There is also a word document versionf for download
If you are a SQL Server 2005 developer/administrator then this is a must read

You will be introduced to new views such as sys.dm_exec_sql_text, sys.dm_exec_cached_plan, Sys.dm_db_index_operational_stats and sys.dm_db_index_usage_stats

Below is a short list of what is covered in the article

Resource Bottlenecks
Tools for resolving resource bottlenecks

CPU Bottlenecks
Excessive compilation and recompilation
Inefficient query plan
Intra-query parallelism
Poor cursor usage

Memory Bottlenecks
External physical memory pressure
External virtual memory pressure
Internal physical memory pressure
Caches and memory pressure
Ring buffers
Internal virtual memory pressure

Tempdb
Monitoring tempdb space
Troubleshooting space issues
User objects
Version store
Internal Objects
Excessive DDL and allocation operations
Resolution

Slow-Running Queries
Blocking
Identifying long blocks
Blocking per object with sys.dm_db_index_operational_stats
Overall performance effect of blocking using SQL waits
Monitoring index usage

Appendix A: DBCC MEMORYSTATUS Description
Appendix B: Blocking Scripts

Read the whole article here (Troubleshooting Performance Problems in SQL Server 2005)

Monday, January 02, 2006

Contact Me

If you want to contact me and let me know that you like this blog or that you hate it or if you have any kind of suggestion then run the code below in Query Analyzer/Managment Studio to get my email (to prevent spam)

SELECT CONVERT(VARCHAR(31),0x73716C736572766572636F646540676D61696C2E636F6D)

SQL Server Site Geo Map For December

Happy New Year

Happy new year to all of you