Using SQL Server 2000 and above versions you can retrieve data from SQL Server in XML format directly from the database. Many XML related features were incorporated in the SQL Server database. This enables the development of XML enabled applications very easy and it makes exchange of data over internet easy. In this article we will discuss about how to use SQLXML to retrieve data directly from SQL server database in XML format.
There are some SQL commands and clauses that help you to retrieve data from the SQL Server in the XML format. Syntax for such is given below:
SELECT ... FOR XML mode [, XMLDATA] [, ELEMENTS] [, BINARY BASE64]
There are different modes and that take the values of
? AUTO ? In this mode every row of the result of the query forms an element in the returned XML document.
? EXPLICIT ? This mode defines how to map the columns of the results returned by the query to the XML elements and the attributes.
? RAW - All the fields of the result are identified as attributes of an element.
? NESTED ? The result of this mode is the same as the AUTO mode but the formatting has to be done at the client side.
A simple example of using the above syntax is given below:
SELECT TOP 3 * FROM (SELECT FirstName+' '+LastName as Name FROM Employees) FOR XML AUTO
The query produces this result:
Employees Name="John Peter"
Employees Name="Andrew Dixon"
Employees Name="Tom Hanks"
There are optional parameters in the 'FOR XML mode' clause. The XMLDATA option adds an XSD schema which describes the XML format of the result returned. The ELEMENTS options make the fields of the tables in the database to be returned as child elements. If the ELEMENTS option is not there the fields of the tables are returned as attributes instead of child elements of the XML document. The ELEMENTS option is allowed only in the AUTO mode. The BINARY BASE64 option is used to retrieve any binary data. The returned binary data is returned in BASE64 encoded format. The binary data can be retrieved in the RAW or EXPLICIT mode.
An example of the RAW mode is given below:
SELECT EmpName, EmpCity from EMP for XML RAW
The above code returns a result like,
row EmpName="John" EmpCity="New York"
In the above result you can note that the fields of the resultset are returned as attributes of the element.
.Net provides with managed classes for interacting with SQL Server. The managed classes of SQLXML provided by .Net are:
? SqlXmlCommand ? This is used to perform queries that are stored in XML documents which are also called XML templates. This class also provides support for client side XML processing.
? SqlXmlParameter ? this is used to provide parameterized values and is used along with SqlXmlCommand object.
? SqlXmlAdapter ? this is the adapter class for SQLXML provider. This is used to fill the dataset.
? SqlXmlException ? this is used to trap the error information from the SQL Server.
A sample code using the managed classes is given below. For detailed information on the usage of the above managed classes you can refer to the MSDN documentation.
static string cstr = "Provider=SQLOLEDB;Server=(local);database=EmpPersonal;"; public static void testingSqlXml () {
Stream oStr = Console.OpenStandardOutput();
SqlXmlCommand sqlcmd = new SqlXmlCommand(cstr);
sqlcmd.Root = "Employees";
sqlcmd.CommandType = SqlXmlCommandType.Sql;
sqlcmd.CommandText = "SELECT EmpName, EmpCity FROM Employees FOR XML AUTO";
strm = sqlcmd.ExecuteToStream(oStr);
oStr.Close(); }
Thus we have seen that SQLXML can be used to retrieve data directly from the SQL Server in XML format. It is easy to handle and transmit data through the internet if it is in the XML format and this can be easily achieved using the SQLXML.
Want to stay current with the latest technology developments realted to XML. Visit free xml tutorial to get your FREE subscription now!
** Attention Webmasters / Website Owners ** You can reprint this article on your website as long as you do not modify any of the content, and include our resource box as listed above with all links intact and hyperlinked properly.
tidy up service Glenview ..Using SQL Server 2000 and above versions you can retrieve... Read More
Surf the 'Net for about 10 minutes and chances rate... Read More
GOT VIRUS? Your Data is NOT lost forever!In the wake... Read More
If you don't have an mp3 player, and even if... Read More
Many computer users are worried about their computer's performance. After... Read More
Are you stymied by the vast offerings in cheap mp3... Read More
Flow Text Around a GraphicQuestion: I have inserted a photo... Read More
There have been some questions on anti-skip protection on mp3... Read More
I'm eighty-one years old and I bought my first computer... Read More
It seems like fast never quite rates fast enough.No matter... Read More
The United States Of America citizen feels that games is... Read More
So I'll start from the very beginning.One day I was... Read More
This is the third in a series of articles highlighting... Read More
ASR (Automated System Recovery) is a feature available on the... Read More
It's hard enough as it is these days to get... Read More
Plasma and LCD TVs are the latest trend in home... Read More
I would like to tell you about a magic home.... Read More
There are many sources of heat that can raise the... Read More
Each of the items in the checklist below is part... Read More
Computers are available in different shapes, sizes and weights, due... Read More
If you use a computer, you need to know more... Read More
Do you use Windows standard uninstall feature? How do you... Read More
Microsoft Certifications are one of the most widely acclaimed, pursued,... Read More
If you have a computer for home use or for... Read More
The technological horizon has always got something new to offer,... Read More
full-service cleaning Mundelein ..Enhanced Definition Television ? also known as EDTV ? is... Read More
BIOS - Basic Input Output SystemThe central processing unit of... Read More
Those small USB drives have so many names, pocket drives,... Read More
Time is money. And when you constantly have to divide... Read More
With the new technology used to transfer information to from... Read More
Yes, it's true. You may have inadvertently invited a spy... Read More
So you've got some spyware, ad-ware, or viruses on your... Read More
Microsoft Business Solutions is on the way to popularize it's... Read More
You use Ctrl+Alt+Del to see what's running on your PC,... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
I am going to assume that you are running windows... Read More
Lost & Found for the 21st CenturyIn today's hectic world... Read More
Wouldn't you be shocked to find that your personal sensitive... Read More
Windows Media Player 10 has been full of bugs from... Read More
How familiar does the following sound? Your computer was working... Read More
Occupational Therapy Made EasierMedical downloads for the pda have improved... Read More
1. Let your PC boot up completely before opening any... Read More
Stop Getting LostOne of the greatest uses for a pocket... Read More
I recently took a good look at what was keeping... Read More
As the web has evolved, so have the methods of... Read More
If you are a building a website or a forum,... Read More
In the years of the dot com boom and bust,... Read More
A computer needs a certain amount of information to operate;... Read More
I have always been interested in computers, but in the... Read More
Digital cameras ratings are great tools for deciding which camera... Read More
Personal Technology |