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.
Ashton group transportation logistics management ..For six years, my Samsung PC 13.8 inch SyncMaster conventional... Read More
I do a holiday letter every year and send them... Read More
There are many sources of heat that can raise the... Read More
As the owner of a Country Mall and Top Site... Read More
You use Ctrl+Alt+Del to see what's running on your PC,... Read More
Addressing a D2X Digital SLRCoolpix 8800 search, this article provides... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
There are soooo many choices. With all the styles and... Read More
Yes, it's true. You may have inadvertently invited a spy... Read More
One of the most common questions computer users ask is,... Read More
I've worked my way from the CCNA to the CCIE,... Read More
Have you ever tried to remove Spyware off your PC... Read More
It seems like fast never quite rates fast enough.No matter... Read More
With their solid-state technology, compact size, and abundant memory, portable... Read More
GOT VIRUS? Your Data is NOT lost forever!In the wake... Read More
Cisco Certification: Taking Your First Certification ExamYou've studied hard; you've... Read More
The Internet is an awesome tool, but be careful and... Read More
Choose Not To ConformPalm pilots and pdas are constantly growing... Read More
In this era of Internet, most people are frequent users... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
Step 1:Open WinRAR and browse to the folder with your... Read More
This is the third in a series of articles highlighting... Read More
If you don't have an mp3 player, and even if... Read More
Most of the web applications have a lot of images... Read More
Not so many years ago, homes across the country watched... Read More
group transportation logistics management Highland ..All over the world, people carry with them walkmans and... Read More
Lost & Found for the 21st CenturyIn today's hectic world... Read More
The best way to get the gaming computer that you... Read More
Just The Facts, Ma'mPalm pilots are all the rage now.... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
If you utilize a computer at home or work it... Read More
"Aaaaaahhhhhh! I've been invaded by a virus!" Getting a virus... Read More
Viruses, software failures, power failures, human errors, hard drive failures... Read More
First and foremost before I begin my ranting it is... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
For many people the computer industry is a seeming unsolvable... Read More
With the bewildering number of digital cameras on the market,... Read More
All of us are familiar with the pyramids of Egypt.... Read More
Upgrading your processor will always speed up your computer, but... Read More
Cameras: still known for taking pictures but assumed as digital... Read More
The following practice, if done regularly, may help you to... Read More
The first step is: Start > My DocumentsSo you have... Read More
Computer is an electronic machine work on the instructions of... Read More
After reading this good article you will know some important... Read More
What is a Refurbished Computer?Refurbished Computers. Remanufactured Computers. Reconditioned Computers.... Read More
Windows Media Player 10 has been full of bugs from... Read More
When I first started studying for my CCNP, some of... Read More
World War II - Germany decided to attack Poland. Poland... Read More
When studying for your Cisco CCNA, CCNP, or CCIE exam,... Read More
After another security hole recently surfaced in Microsoft's Windows operating... Read More
Personal Technology |