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.
disinfecting cleaning services Arlington Heights ..Feeling overwhelmed in selecting a new TV? With all the... Read More
In this era of Internet, most people are frequent users... Read More
OK, so you caught a computer virus and your system... Read More
File Transfer Protocol (FTP) is a protocol that is part... Read More
Winter?the official start of the cold and flu season. Though,... Read More
Passwords have a strange dual nature. The stronger and safer... Read More
Saving Lives With A Pocket PCFree medical downloads can be... Read More
I do a holiday letter every year and send them... Read More
Sometimes your PC will start acting strange for no apparent... Read More
The DNS (Domain Name System) servers are what your computer... Read More
MMC and SDFlash memory is available in so many formats... Read More
This article describes the basic properties of color, what the... Read More
Do you know how many fonts are currently installed on... Read More
Do you remember the old saw about how computers would... Read More
Computers are available in different shapes, sizes and weights, due... Read More
In Windows Xp, you can install two operating systems on... Read More
You don't have to fork out $250 for a super-diggy-whizbang... Read More
Are you thinking of buying an Apple iPod? Or have... Read More
You???ve studied hard; you???ve practiced your configurations; you???ve used your... Read More
Windows Media Player 10 has been full of bugs from... Read More
Perhaps not yet, but the handwriting might be on the... Read More
What is a Refurbished Computer?Refurbished Computers. Remanufactured Computers. Reconditioned Computers.... Read More
If you ask most people what frustrates them most about... Read More
Introduction In this article I will clearly spell out the... Read More
I've worked my way from the CCNA to the CCIE,... Read More
bathroom cleaning service Mundelein ..There are soooo many choices. With all the styles and... Read More
When browsing the internet you are likely to come across... Read More
The first step is: Start > My DocumentsSo you have... Read More
Flash mp3 players come with an exciting array of features,... Read More
Are you thinking of buying an Apple iPod? Or have... Read More
Plenty! When we made the decision to be our own... Read More
I have a love-hate relationship with my computer.In fact, often... Read More
I recently got an e-mail asking about virtual memory. The... Read More
If you're a computer expert, you'll probably already know about... Read More
First things first, what is Firefox? Well, it's a browser.... Read More
Confused by EDTV vs HDTV? We don't blame you. The... Read More
Your first step in removing dangerous infections from your computer... Read More
We have just entered the time of year that most... Read More
Computers are supposed to speed up our productivity?to help us... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
As the owner of a Country Mall and Top Site... Read More
Projectors have come a long way in the past few... Read More
"Automated Testing" is automating the manual testing process currently in... Read More
Introduction In this article I will clearly spell out the... Read More
We've all seen them, you've been browsing a website and... Read More
It's free, it comes with Windows and it's used by... Read More
1. Before sitting down for coding, you must have formal... Read More
It seems like fast never quite rates fast enough.No matter... Read More
There are many sources of heat that can raise the... Read More
Getting a new computer should be an exciting and gratifying... Read More
Personal Technology |