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.
green cleaning service Park Ridge ..First things first, what is Firefox? Well, it's a browser.... Read More
We've all seen them, you've been browsing a website and... Read More
I got my eyes set on a iPod mini, as... Read More
Has This Ever Happened To You? OK.. it's Friday night,... Read More
Computer is an electronic machine work on the instructions of... Read More
Flow Text Around a GraphicQuestion: I have inserted a photo... Read More
Computers are everywhere, and vary in specification, brands, sizes, shaped,... Read More
Plasma and LCD TVs are the latest trend in home... Read More
OK, so you caught a computer virus and your system... Read More
Computers are available in different shapes, sizes and weights, due... Read More
You don't have to fork out $250 for a super-diggy-whizbang... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
I do a holiday letter every year and send them... Read More
We all enjoy our favorite screensavers but in the same... Read More
Below you will find some useful information and comments about... Read More
Buying Your PCBuying a PC that's right for you and... Read More
A computer needs a certain amount of information to operate;... Read More
System File Checker is a great utility that is typically... Read More
Most people download and save so much information on their... Read More
So you got yourself a digital camcorder. If you want... Read More
JPEG, GIFF/JIFF, BMP, and TIFF are the most commonly used... Read More
Winter?the official start of the cold and flu season. Though,... Read More
As the web has evolved, so have the methods of... Read More
cleaning help near Bannockburn ..When you turn on your computer, does it act like... Read More
On 21 August 2003 Symantec Security Response upgraded the W32.SOBIG.F... Read More
Introduction In this article I will clearly spell out the... Read More
Plenty! When we made the decision to be our own... Read More
Confused by EDTV vs HDTV? We don't blame you. The... Read More
If you're like me, you occasionally find the ubiquitous mouse... Read More
The Cisco Certified Network Associate (CCNA) Certification is meant for... Read More
Music lovers have been carrying around radios and other bulky... Read More
I have a love-hate relationship with my computer.In fact, often... Read More
System File Checker is a great utility that is typically... Read More
"Automated Testing" is automating the manual testing process currently in... Read More
For many people the computer industry is a seeming unsolvable... Read More
1. Let your PC boot up completely before opening any... Read More
You don't have to fork out $250 for a super-diggy-whizbang... Read More
One of the most common questions computer users ask is,... Read More
We have just entered the time of year that most... Read More
We all enjoy our favorite screensavers but in the same... Read More
JVC developed and used a high-performance reflective film to produce... Read More
When I first started studying for my CCNP, some of... Read More
The first step is: Start > My DocumentsSo you have... Read More
You???ve studied hard; you???ve practiced your configurations; you???ve used your... Read More
For six years, my Samsung PC 13.8 inch SyncMaster conventional... Read More
Digital cameras ratings are great tools for deciding which camera... Read More
There are plenty of articles out there about how to... Read More
Your first step in removing dangerous infections from your computer... Read More
Personal Technology |