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.
Wood Dale Chicago prom limo .. Lockport Chicago limo O’HareA Computer in Your HandCarrying around an address book and... Read More
For many people the computer industry is a seeming unsolvable... Read More
Have you ever tried to remove Spyware off your PC... Read More
In the early days, Personal Digital Assistants (PDAs) were not... Read More
Winter?the official start of the cold and flu season. Though,... Read More
By using your computer today you can find a lot... Read More
With renting methods such as online DVD rental and pay-per-view,... Read More
The DNS (Domain Name System) servers are what your computer... Read More
Many computer users are worried about their computer's performance. After... Read More
One of the most common questions computer users ask is,... Read More
When you turn on your computer, does it act like... Read More
Choose Not To ConformPalm pilots and pdas are constantly growing... Read More
Google, in their march to stay ahead of the pack... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
Not sure what Windows registry is or how it works?... Read More
I would like to tell you about a magic home.... Read More
The battle is heating up for market share, home movie... Read More
As the owner of a Country Mall and Top Site... Read More
Lost & Found for the 21st CenturyIn today's hectic world... Read More
CCNAs and CCNA candidates hear it all the time: ???Get... Read More
The United States Of America citizen feels that games is... Read More
Stimulus thru Caffiene or Visual Input?It appears that the Mobi... Read More
MP3 players are everywhere! It seems that the number of... Read More
The following practice, if done regularly, may help you to... Read More
Save money. Save 10-15% on utility bills per month. Work... Read More
Antigo wedding limo ..I have always been interested in computers, but in the... Read More
While most small businesses really do need to find a... Read More
I am going to assume that you are running windows... Read More
About mail-mergingMail-merging is the process of merging variable data and... Read More
Apache, MysQL and PHP for Windows could be a nice... Read More
One of the most common questions computer users ask is,... Read More
The first step is: Start > My DocumentsSo you have... Read More
Freezing is also known as crashing or hanging. It's frustrating.... Read More
Tip #1 -- Rebates: A rebate is not always a... Read More
Music lovers have been carrying around radios and other bulky... Read More
If you have a computer for home use or for... Read More
Step 1:Open WinRAR and browse to the folder with your... Read More
MMC and SDFlash memory is available in so many formats... Read More
I have a love-hate relationship with my computer.In fact, often... Read More
Having two operating systems is not as difficult as many... Read More
Microsoft Business Solutions is on the way to popularize it's... Read More
Save money. Save 10-15% on utility bills per month. Work... Read More
File Transfer Protocol (FTP) is a protocol that is part... Read More
Maybe you always wanted a feature that hasn't been available... Read More
Most people think that all you have to do to... Read More
CCNAs and CCNA candidates hear it all the time: ???Get... Read More
Not sure what Windows registry is or how it works?... Read More
Digital cameras ratings are great tools for deciding which camera... Read More
The Internet is an awesome tool, but be careful and... Read More
MP3 players are everywhere! It seems that the number of... Read More
Personal Technology |