Peter W. DeBetta

OT: What will Bill Gates do after he leaves Microsoft?

I laughed, I cried...

http://video.msn.com/video.aspx?mkt=en-US&brand=&vid=27db94c9-4892-4059-8688-f4afd3c4b64a

Bill Gates presents a farewell video at the keynote of the Consumer Electronics Show.

Cross-posted from SQLBlog! - http://www.sqlblog.com

TechEd2008 Abstract Deadline Extension

Just over a month ago, Simon Guest had posted a blog entry about the call for sessions for TechEd 2008. The original deadline was 31 December 2007, but I've just gotten confirmation that this deadline has been extended to 31 January 2008, so if you were thinking of submitting any abstracts, you still have some time to do it.

To get started, you need to first go to https://2008.msteched.com/cft/. Use TEUS-Speakers as the access code, create a profile, and begin submitting topics.

Cross-posted from SQLBlog! - http://www.sqlblog.com

2008: Converting XML to HIERARCHYID

While working on a new book, I have been experimenting with the new HIERARCHYID data type. And since I've seen comparisons drawn between using XML versus using HIERARCHYID to manage a hierarchy of data, I decided that it would likely be very useful if I could convert an XML structure into an equivalent relational structure using HIERARCHYID. Here is what I came up with:

DECLARE @x XML =

'<A id="1">

</A>';

WITH Folders AS

(

SELECT

t.c.value('@id', 'int') AS ID

, NULLIF(t.c.value('../@id', 'nvarchar(50)'), '') AS ParentID

, t.c.value('local-name(.)', 'nvarchar(50)') AS Description

, t.c.value('for $s in . return count(../*[. << $s]) + 1', 'int') AS RowNum

FROM @x.nodes('//*') AS t(c)

)

, FolderTree AS

(

SELECT ID, ParentID, Description, RowNum,

HIERARCHYID::GetRoot() AS FolderNode

FROM Folders

WHERE ParentID IS NULL

UNION ALL

SELECT F.ID, F.ParentID, F.Description, F.RowNum,

CAST(FT.FolderNode.ToString() + CAST(F.RowNum AS varchar(50)) + '/'

AS HIERARCHYID)

FROM Folders AS F

INNER JOIN FolderTree AS FT ON F.ParentID = FT.ID

)

SELECT

ID,

ParentID,

Description,

FolderNode,

FolderNode.ToString() AS Path

FROM FolderTree

ORDER BY FolderNode;

Which results in:

ID	ParentID	Description	FolderNode	Path
1	NULL	A	0x	/
2	1	B	0x58	/1/
3	2	C	0x5AC0	/1/1/
4	2	D	0x5B40	/1/2/
5	1	E	0x68	/2/
6	1	F	0x78	/3/

The basis of this is the same as if converting an existing adjacency model to use HIERARCHYID – use a combination of a recursive CTE and row numbers partitioned by parent to generate the new path of the node and then cast that path to the HIERARCHYID data type. The parent path is retrieved using the ToString method of the parent node, and this is concatenated with the RowNum value and a forward slash (/) to result in the path for the current node. And finally, the newly generated path is then cast to HIERARCHYID, which uses its static Parse method behind the scenes to create a new instance of HIERARCHYID. This table shows the additional detail and should reveal how the new path is created.

ID	ParentID	Description	FolderNode	Path	Parent Path	RowNum
1	NULL	A	0x	/	*N/A*	1
2	1	B	0x58	/1/	/	1
3	2	C	0x5AC0	/1/1/	/1/	1
4	2	D	0x5B40	/1/2/	/1/	2
5	1	E	0x68	/2/	/	2
6	1	F	0x78	/3/	/	3

On the XML side of things, I generated a partitioned row number by using the nodes method to return all nodes in the XML structure, as shown here: FROM @x.nodes('//*') AS t(c). The double forward slash (//) translates to "relative path" and the asterisk means any node, so this returns all nodes at all levels. Then, to return the row number, I use one of my favorite XQuery examples:

t.c.value('for $s in . return count(../*[. << $s]) + 1', 'int') AS RowNum

This translates to "count the number of immediate child nodes of my parent node that are positioned before me." Now that I have all the nodes, and a partitioned row number for these nodes, I can construct the new path of the node.

I will post more as I continue writing about and exploring SQL Server 2008.

Enjoy!

Cross-posted from SQLBlog! - http://www.sqlblog.com

Row Constructor or Table-Valued Parameter

Denis posted a follow-up to the posts by both Louis and me. However, I have to say that there is a better way to pass a bunch of data to a procedure. The following code is amended to include the table-valued parameter feature.

--The Movie Table

CREATE TABLE Movie

(

MovieID INT IDENTITY(1, 1),

MovieRatingId INT,

Title VARCHAR(200) NOT NULL

);

INSERT INTO Movie (MovieRatingId, Title)

VALUES

(3, 'SQL the Movie'),

(4, 'SQL Massacre'),

(1, 'SQL for Everyone'),

(4, 'SQL Massacre 2 - The Oracle Returns');

--Create a new table type in the database

CREATE TYPE MovieRating AS

TABLE (

MovieRatingId int NOT NULL,

Code varchar(20) NOT NULL,

Description varchar(200) NULL,

AllowYouthRentalFlag bit NOT NULL

)

--Create a new proc that accepts a table as a parameter

CREATE PROC prMoviesByRating

(

@MovieRatings MovieRating READONLY

)

BEGIN

--and join to that table-valued parameter

SELECT

M.Title,

MR.Code AS RatingCode,

MR.Description AS RatingDescription

FROM Movie AS M

INNER JOIN @MovieRatings AS MR

ON M.MovieRatingId = MR.MovieRatingId;

END

--Declare a variable using our table type

DECLARE @MovieRatings MovieRating

--and insert data into it (again, using a row constructor)

INSERT INTO @MovieRatings

VALUES

(0, 'UR','Unrated',1),

(1, 'G','General Audiences',1),

(2, 'PG','Parental Guidance',1),

(3, 'PG-13','Parental Guidance for Children Under 13',1),

(4, 'R','Restricted, No Children Under 17 without Parent',0)

--and pass the table as parameter to the proc...

EXEC prMoviesByRating @MovieRatings

So when I want to pass the data in, no dynamic SQL is necessary, since I can instead simply pass the table itself (with all of its data)…

Cross-posted from SQLBlog! - http://www.sqlblog.com

2008: More Row Constructor Fun

My esteemed colleague Louis Davidson just wrote about a new feature in SQL Server 2008 known as row constructors. I thought I'd follow up with some more fun usage of this cool feature. In addition to being used with an INSERT statement, you can also use a row constructor in a common table expression (CTE). This example uses the row constructor to insert data into one table (@Movie) and then again to join a table to another sets of constructed row:

DECLARE @Movie TABLE
(
    MovieID INT IDENTITY(1, 1),
    MovieRatingId INT,
    Title VARCHAR(200) NOT NULL
);

INSERT INTO @Movie (MovieRatingId, Title)
VALUES
    (3, 'SQL the Movie'),
    (4, 'SQL Massacre'),
    (1, 'SQL for Everyone'),
    (4, 'SQL Massacre 2 - The Oracle Returns');

WITH MovieRatings (MovieRatingId, Code, Description, AllowYouthRentalFlag)
AS
(    SELECT *
    FROM (VALUES
        (0, 'UR','Unrated',1),
        (1, 'G','General Audiences',1),
        (2, 'PG','Parental Guidance',1),
        (3, 'PG-13','Parental Guidance for Children Under 13',1),
        (4, 'R','Restricted, No Children Under 17 without Parent',0))
            AS MR(MovieRatingId, Code, Description, AllowYouthRentalFlag)
)
SELECT
    M.Title,
    MR.Code AS RatingCode,
    MR.Description AS RatingDescription
FROM @Movie AS M
    INNER JOIN MovieRatings AS MR
        ON M.MovieRatingId = MR.MovieRatingId;

Notice that when used in a CTE, the syntax is slightly different

SELECT column_list
FROM
(VALUES
(column_1_value [, column_2_value [, ...]])
(column_1_value [, column_2_value [, ...]])
) AS TableAlias (column_1_name [, column_2_name [, ...]])

When used in a CTE, you must supply a table alias, as well as column names for all columns supplied by the row constructor.

Enjoy!

Cross-posted from SQLBlog! - http://www.sqlblog.com

Non-Technical: SQLblog has moved!

If you are reading this post then you are being served up by SQLblog from its new home at MaximumASP hosting provider. We are very excited to be working with the people at MaximumASP in order to better serve the community and help with the continuing growth of SQLblog.

Cross-posted from SQLBlog! - http://www.sqlblog.com

SQL Server Connection Level Parameters

Have you ever needed to pass in a value that would be used throughout the lifetime of a connection - perhaps a connection session level value that would be used by multiple procedures, views, functions, etc...?

Well, a colleague of mine, Jay Frysinger, had a great idea - use the connection string itself to pass additional parameters. You can use both "Application Name" and "Workstation ID" to pass in 2 additional 128 character length strings. You can then use the APP_NAME() system function to retrieve the value of the "Application Name" or the HOST_NAME() system function to retrieve the value of "Workstation ID".

In this example, a GUID is created in the data client, then using ToString() of the GUID, it is added to the connection string. Then, HOST_NAME() is used to extract that value. Since I wanted a UniqueIdentifier in SQL, I used CAST to convert the string GUID to a UniqueIdentifier. Finally, the UniqueIdentifier is returned and displayed in the console.

using System; using System.Data; using System.Data.SqlClient; namespace ConnectionStringTest { class Program { static void Main(string[] args) { Guid guid = new Guid("BCAEF7EA-7BD3-4CC8-8288-9B2C8F6BCF28"); using (SqlConnection c = new SqlConnection(string.Format (@"Data Source=YourServer;Initial Catalog=YourDatabase;Persist Security Info=True;Trusted_Connection=True;Workstation ID={0}", guid.ToString()))) { using (SqlCommand cmd = new SqlCommand("SELECT CAST(HOST_NAME() as uniqueidentifier)", c)) { cmd.CommandType = CommandType.Text; c.Open(); SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection); while (dr.Read()) { Console.WriteLine(dr.GetSqlGuid(0).ToString()); } dr.Close(); } c.Close(); } Console.ReadLine(); } } }

Cross-posted from SQLBlog! - http://www.sqlblog.com

Manage Visual Studio Auto Connect to Team Foundation Server

I've been on a project where we are using Team Foundation Server (TFS). As you may already be aware, Visual Studio (VS) automatically tries to connect to TFS. When I am onsite, this is great, but when I am offsite and not VPN-ed into the client site, VS takes a long time to time out on its attempt to connect to their TFS. When going in and out of VS throughout the day, I felt as if I was wasting a lot of time waiting for VS to time out. So I found this little nugget that showed how to modify the registry to turn off the auto connect feature:

http://blogs.conchango.com/merrickchaffer/archive/2007/01/09/Prevent-Visual-Studio-Team-Explorer-from-connecting-to-Team-Foundation-Server-at-startup.aspx

But I decided that I wanted to quickly be able to change the setting without having to plow through the registry each time, and so I wrote a quickie VBScript for WSH that would allow you to easily change the registry setting. Here is that script:

' VBScript 
' The script creates and/or updates the TFS AutoLoadServer feature for Visual Studio 
' By default, Visual Studio will attempt to reconnect to all Team Foundation Servers 
'  
' Creating a REG_DWORD value named AutoLoadServer at  
' HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\8.0\TeamFoundation\ 
' you can manually control whether or not VS will automatically connect to TFS server(s)  
' 0 means do not automatically connect  
' 1 means automatically connect (default behavior when value is not present) 
' 
' Peter DeBetta, 2007 

' Some variables 
Dim objShell, RegLocation 

' Instantiate the WSH Shell 
Set objShell = WScript.CreateObject("WScript.Shell") 

' This is the value that affects the auto connect feature 
RegLocation= "HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\8.0\TeamFoundation\AutoLoadServer" 

' Ask for the new value (default to "1") 
id = inputbox("Type 1 to turn on, 0 to turn off","VS TFS AutoLoadServer", "1") 


If id <> "0" And id <> "1" Then 
   ' Did we get a valid value? No? Then let the user know 
   objshell.popup "Invalid input: Only 0 or 1 are allowed" ,,"INPUT ERROR!",48 
Else 
   ' Otherwise, update the Registry Value 
   objShell.RegWrite RegLocation, id, "REG_DWORD" 
End If 

' Exit Gracefully 
WScript.Quit

Cross-posted from SQLBlog! - http://www.sqlblog.com

DevTeach Code Samples

A little overdue, here are my code samples from my sessions at DevTeach Montreal 2007.

Cross-posted from SQLBlog! - http://www.sqlblog.com

News: DevTeach, TechEd, and SQLblog Sundries...

I know I have been a slacker when it comes to posting lately, but I have been on the road quite a bit of late and will finally have some time at home over the next 2 weeks and have some new topics that I should be posting about during that time.

As for DevTeach, SQLblog had a great presence at the SQLTeach part of the conference here in Montreal, including (in no particular order): Adam Machanic, Kevin Kline, Rick Heiges, Paul Nielsen, Roman Rehak (who was the SQLTeach Tech Chair), and yours truly, and soon to be blogging at SQLblog, James Luetkehoelter. I heard great things about my fellow SQLbloggers and was glad to get some time to catch up with them and a few other folks at the conference.

As for TechEd. I will be off to TechEd this year (June 4 - 8), and even doing a breakout session on XML in SQL Server 2005. I'll also be co-hosting an SQL Server 2005 XML Q&A session with Michael Rys from Microsoft. Very exciting!

Finally, I will be looking into migrating SQLblog to the latest version of CommunityServer (CS2007) in the coming months. With the change, we are also hoping to add some new features to the site. Some of the features we have been contemplating are articles, book reviews, and voting forums. No promises; but when my current project ends, I hope to have time to implement some of these features (assuming CS2007 makes it easy to do so).

Cross-posted from SQLBlog! - http://www.sqlblog.com

T-SQL Convert Hex String to Varbinary

One last post before I go on vacation next week...

SQL Server 2005 includes an undocumented function, sys.fn_varbintohexstr, that converts a hex value to a string representation of that hex value (0x3a becomes '0x3a'), but there is no function to go back from a hex string to a hex value. Now there is J:

CREATE FUNCTION dbo.HexStrToVarBin(@hexstr varchar(8000))

RETURNS varbinary(8000)

BEGIN

DECLARE @hex char(2), @i int, @count int, @b varbinary(8000)

SET @count = LEN(@hexstr)

SET @b = CAST('' as varbinary(1))

IF SUBSTRING(@hexstr, 1, 2) = '0x'

SET @i = 3

ELSE

SET @i = 1

WHILE (@i <= @count)

BEGIN

SET @hex = SUBSTRING(@hexstr, @i, 2)

SET @b = @b +

CAST(CASE WHEN SUBSTRING(@hex, 1, 1) LIKE '[0-9]'

THEN CAST(SUBSTRING(@hex, 1, 1) as int)

ELSE CAST(ASCII(UPPER(SUBSTRING(@hex, 1, 1)))-55 as int)

END * 16 +

CASE WHEN SUBSTRING(@hex, 2, 1) LIKE '[0-9]'

THEN CAST(SUBSTRING(@hex, 2, 1) as int)

ELSE CAST(ASCII(UPPER(SUBSTRING(@hex, 2, 1)))-55 as int)

END as binary(1))

SET @i = @i + 2

END

RETURN @b

END

Cross-posted from SQLBlog! - http://www.sqlblog.com

T-SQL UrlDecode

While I'm at it, here is the counterpart to the UrlEncode function – UrlDecode:

CREATE FUNCTION dbo.UrlDecode(@url varchar(3072))

RETURNS varchar(3072)

BEGIN

DECLARE @count int, @c char(1), @cenc char(2), @i int, @urlReturn varchar(3072)

SET @count = Len(@url)

SET @i = 1

SET @urlReturn = ''

WHILE (@i <= @count)

BEGIN

SET @c = substring(@url, @i, 1)

IF @c LIKE '[!%]' ESCAPE '!'

BEGIN

SET @cenc = substring(@url, @i + 1, 2)

SET @c = CHAR(CASE WHEN SUBSTRING(@cenc, 1, 1) LIKE '[0-9]'

THEN CAST(SUBSTRING(@cenc, 1, 1) as int)

ELSE CAST(ASCII(UPPER(SUBSTRING(@cenc, 1, 1)))-55 as int)

END * 16 +

CASE WHEN SUBSTRING(@cenc, 2, 1) LIKE '[0-9]'

THEN CAST(SUBSTRING(@cenc, 2, 1) as int)

ELSE CAST(ASCII(UPPER(SUBSTRING(@cenc, 2, 1)))-55 as int)

END)

SET @urlReturn = @urlReturn + @c

SET @i = @i + 2

END

ELSE

BEGIN

SET @urlReturn = @urlReturn + @c

END

SET @i = @i +1

END

RETURN @urlReturn

END

Cross-posted from SQLBlog! - http://www.sqlblog.com

T-SQL UrlEncode

I was perusing the newsgroups when I came across a request in the microsoft.public.sqlserver.clr newsgroup to see if there was a way to use System.Web.HttpUtility.UrlEncode in T-SQL. I know using the CLR is an option, but I decided to write a T-SQL equivalent. I reflected the code to figure out the exact rules for UrlEncoding. Then, I discovered much to my delight, a new system function in SQL Server 2005 that converts a string to its hexadecimal equivalent as a string– sys.fn_varbintohexstr. I knew there was an extended stored procedure in prior versions of SQL Server to do this conversion, but this function made writing this UrlEncode function even easier.

CREATE
				FUNCTION dbo.UrlEncode(@url varchar(1024))

RETURNS
				varchar(3072)

AS


				BEGIN

    DECLARE @count int, @c char(1), @i int, @urlReturn varchar(3072)

    SET @count =
				Len(@url)

    SET @i = 1

    SET @urlReturn =
				''

    WHILE
				(@i <= @count)

     BEGIN

        SET @c =
				substring(@url, @i, 1)

        IF @c LIKE
				'[A-Za-z0-9()''*-._! ]'

         BEGIN

            SET @urlReturn = @urlReturn + @c

END

        ELSE

         BEGIN

            SET @urlReturn =

                @urlReturn +

                '%'
				+

                SUBSTRING(sys.fn_varbintohexstr(CAST(@c as
				varbinary(max))),3,2)

END

        SET @i = @i +1

END

    RETURN @urlReturn

END

GO

This function works in a very similar fashion to the UrlEncodeBytesToBytesInternal found in the .NET Framework (in System.Web.HttpUtility) except that the function I wrote does not convert the URL to a byte array. If you have the latest version of Reflector, you can view the reflected code for UrlEncodeBytesToBytesInternal here.

And speaking of Reflector – if you have the latest version, you can copy a URL link to a method, class, property, and so on by select the item and pressing Ctrl-Alt-C (which is how I put that link in this post).

Cross-posted from SQLBlog! - http://www.sqlblog.com

DevWeek Downloads

For all those who attemeded any of my talks at DevWeek In London last week, I have included any changed slide decks and code samples in the attached zip file (at bottom of post).

Enjoy!

Cross-posted from SQLBlog! - http://www.sqlblog.com

Multiple-Valued Parameters

So I was doing some research on which is the best way to pass multiple-valued parameters into a stored procedure or user-defined function when I found some interesting results. I had always used a string-based user-defined function to parse a delimited list of values and I knew I could use XML to do the same thing, yet I had never compared the two side-by-side to see which is a better choice.

So which was faster? Well, using one of many available string-based UDFs, I had unexpected results. I thought that the XML version would be equivalent if not slower, but alas, I was wrong. The XML-based UDF consistently performed about 35% faster than the string-based inline table-valued UDF and about 65% faster than string-based table-valued UDF I tested.

I will be following-up this post soon with a post about various XML-based techniques that I tested…

As for now, here are the various functions used in the tests:

CREATE FUNCTION dbo.fnString2IntList(@sData varchar(8000), @sDelim char(1))
RETURNS @tList TABLE (ListValue int)
AS
BEGIN
    DECLARE @sTemp int, @nPos int, @nPos2 int
    IF (Len(RTrim(LTrim(@sData))) = 0) RETURN

    SET @nPos = CharIndex(@sDelim, @sData, 1)

    IF @nPos = 0 OR @nPos = Len(@sData)
     BEGIN
        SET @sTemp = CAST(SubString(@sData, 1, (Len(@sData) - Sign(@nPos))) as int)
        INSERT INTO @tList VALUES(@sTemp)
        RETURN
     END

    SET @sTemp = CAST(SubString(@sData, 1, @nPos - 1) as int)
    INSERT INTO @tList VALUES(@sTemp)

    WHILE @nPos > 0
     BEGIN
        SET @nPos2 = CharIndex(@sDelim, @sData, @nPos + 1)
        IF (@nPos2 = 0) SET @sTemp = CAST(SubString(@sData, @nPos + 1, Len(@sData)) as int)
        ELSE SET @sTemp = CAST(SubString(@sData, @nPos + 1, ABS(@nPos2 - @nPos - 1)) as int)

        INSERT INTO @tList VALUES(@sTemp)
        SET @nPos = CharIndex(@sDelim, @sData, @nPos + 1)
     END
    RETURN
END
GO

CREATE FUNCTION dbo.fnString2IntList2(@sData varchar(8000), @sDelim char(1))
RETURNS TABLE
AS
 RETURN
 (WITH csvtbl(i,j)
 AS
 (
 SELECT i = 1, j = CHARINDEX(@sDelim, @sData + @sDelim)
 UNION ALL
 SELECT i = j + 1, j = CHARINDEX(@sDelim, @sData + @sDelim, j + 1)
 FROM csvtbl
 WHERE CHARINDEX(@sDelim, @sData + @sDelim, j + 1) <> 0
 )
 SELECT CAST(SUBSTRING(@sData, i, j - i) as int) AS ListValue
 FROM csvtbl)
GO

/* Assumes XML is as such
 <list>
 1
 23
 </list>
 etc...

 Uses minimal xml markup to keep input size as small as possible
*/
ALTER FUNCTION dbo.fnXml2IntList(@xmlList xml)
RETURNS TABLE
AS
 RETURN (SELECT tList.ListValue.value('.', 'int') AS ListValue
 FROM @xmlList.nodes('list/i') AS tList(ListValue))
GO

Cross-posted from SQLBlog! - http://www.sqlblog.com