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.
detailed home cleaning Lake Forest ..Most of the web applications have a lot of images... Read More
I am going to assume that you are running windows... Read More
One of the most confusing parts of beginning your Cisco... Read More
One of the most common questions computer users ask is,... Read More
Computer related terminology could sometimes be daunting to newcomers. These... Read More
Music lovers have been carrying around radios and other bulky... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
Below you will find some useful information and comments about... Read More
Introduction In this article I will clearly spell out the... Read More
Unless you place your faith in internal search engine software... Read More
The Internet can be a dangerous place.While you're enjoying the... Read More
Have you ever tried to remove Spyware off your PC... Read More
With the bewildering number of digital cameras on the market,... Read More
The DNS (Domain Name System) servers are what your computer... Read More
PDA Medical BenefitsIf you are concerned about your medical history,... Read More
Having two operating systems is not as difficult as many... Read More
We all enjoy our favorite screensavers but in the same... Read More
When browsing the internet you are likely to come across... Read More
The Cisco Certified Network Associate (CCNA) Certification is meant for... Read More
This article describes the basic properties of color, what the... Read More
For those seeking to buy their first flat panel TV... Read More
JVC developed and used a high-performance reflective film to produce... Read More
Wouldn't you be shocked to find that your personal sensitive... Read More
Getting a new computer should be an exciting and gratifying... Read More
You probably heard of the new Firefox browser version 1.0... Read More
trusted cleaning company Des Plaines ..This article describes the basic properties of color, what the... Read More
Save money. Save 10-15% on utility bills per month. Work... Read More
It seems like fast never quite rates fast enough.No matter... Read More
As the Web grows more crowded and just plain "noisy"... Read More
All over the world, people carry with them walkmans and... Read More
There are many sources of heat that can raise the... Read More
Many computer users are worried about their computer's performance. After... Read More
The first step is: Start > My DocumentsSo you have... Read More
Have you ever tried to remove Spyware off your PC... Read More
Google, in their march to stay ahead of the pack... Read More
IntroductionMac OS X is the most technologically advanced operating system... Read More
Do you know how many fonts are currently installed on... Read More
Although there are many things that can affect the performance... Read More
The technological horizon has always got something new to offer,... Read More
Understanding digital camera prices makes finding the best camera value... Read More
When studying for your Cisco CCNA, CCNP, or CCIE exam,... Read More
For six years, my Samsung PC 13.8 inch SyncMaster conventional... Read More
Wouldn't you be shocked to find that your personal sensitive... Read More
First things first, what is Firefox? Well, it's a browser.... Read More
This is not your typical lost data story. I was... Read More
Computers are supposed to speed up our productivity?to help us... Read More
Confused by EDTV vs HDTV? We don't blame you. The... Read More
Each of the items in the checklist below is part... Read More
Selecting a TV isn't as easy as it used to... Read More
You will need the following:1. 1.44MB FDD (floppy)2. NVFLASH utility... Read More
Personal Technology |