Integrating XML with Microsoft SQL Server ©NIITeXtensible Markup Language/Lesson 9/Slide 1 of 31...

Integrating XML with Microsoft SQL Server

©NIIT eXtensible Markup Language/Lesson 9/Slide 1 of 31

Objectives

In this lesson, you will learn to:

Generate an XML document by using data stored in SQL Server

Execute XPath queries against data stored in a SQL Server database

Insert XML data in a SQL Server database table



Getting Started

SQL Server 2000 has introduced features for integrating XML with SQL Server.

Some of these features are:

XPath queries

Direct URL queries

The OpenXML function

The FOR XML clause



Problem Statement 9.D.1The details about the products sold at CyberShoppe are stored in a SQL Server 2000 database. This data needs to be displayed in a Web browser.



Task List

Identify the mechanism for generating an XML document.

Build the query for generating the XML document.

Execute the query.



Task 1: Identify the mechanism for generating an XML document.

SQL Server provides the SQL-XML mapping rules for extracting XML data from a database and storing XML data in the database.

The FOR XML clause of the SELECT statement is used to extract data from a database and display it as an XML document.

You can retrieve data in three different modes by using the FOR XML clause.

AUTO

RAW

EXPLICIT



Task 1: Identify the… XML document. (Contd.)

The syntax for using the FOR XML clause in the SELECT statement is as follows:

SELECT table1.column_name1, table2.column_name2

FROM table1, table2

FOR XML mode

Result

You can use the FOR XML clause of the SELECT statement to generate an XML document and display it in a browser.



Task 2: Build the query for generating the XML document.

You need to create a URL query to display the XML document in a browser.

A URL query allows you to embed a SELECT statement along with the URL of a Web server to generate an XML document with the required data.

The syntax of a URL query is as follows:

http://<Server-name>/<vdir>?sql=<sql-statement>&root=rootelementname



Task 2: Build the … XML document. (Contd.)

Result

To display the data stored in a SQL Server 2000 database, you need to create a URL query. To be able to execute the URL query, you need to create a Web site and map the virtual directory of the Web site to the SQL Server database.



Task 3: Execute the query.



Just a Minute…

What are the three modes that can be used with the FOR XML clause?



Just a Minute…

The books table contains the details about the books sold at CyberShoppe. Write a query to generate an XML document based on the data stored in the books table. Also ensure that all columns from the table are displayed as elements and not attributes.



Just a Minute…

Identify the error in the following URL query.

http://localhost/EMPLOYEES?sql=SELECT+*+FROM+EMPLOYEES FOR XML AUTO&root=root



Problem Statement 9.D.2

The details about the toys sold at CyberShoppe need to be displayed in a Web browser. The details are stored in the products table of the CyberShoppe database on SQL Server 2000. The CATEGORY column of the products table indicates the category of a product.



Task List

Identify the method for converting only selective data.

Create an XML schema.

Build a query.

Execute the query.



Task 1: Identify the method for converting only selective data.

SQL Server 2000 allows you to generate an XML document based on the data stored in a database.

You can use the FOR XML clause of the SELECT statement to generate an XML document and display it in a browser.

You can use XPath query to restrict the results returned in an XML document.

XPath query is an XML-based query language that can be used to process the data in an XML document.

To be able to use XPath queries, you need to create an XML schema.

XML Data Reduced language (XDR) is used to describe the content of an XML document.



Task 1: Identify the method …data. (Contd.)

Result

To display only selective nodes from the resulting XML document, you can use XPath query. XPath queries use XML schemas for determining the structure of the XML document and traversing through various nodes. Therefore, you need to create an XML schema. Since SQL Server 2000 supports XDR schema language, you need to create a schema by using XDR.



Task 2: Create an XML schema.

The schema Element

Is the root element used in a file containing the schema for XML documents.

Marks the beginning of a schema definition.

The syntax for this element is as follows:

<Schema xmlns=“namepspace”>



Task 2: Create an XML schema. (Contd.)

The ElementType Element

Allows you to create an element type that can be used in a schema.

The syntax for the ElementType element of XDR is as follows:

<ElementType content=”{eltOnly | textOnly | empty | mixed}” dt:type=”datatype” model=”{open | closed}” name=”name” order=”{one | seq | many }”>

Content Model Declaration

</ElementType>




The AttributeType Element

Allows you to declare an attribute type, which can be used later in the schema.

The syntax for the AttributeType element of XDR is as follows:

<AttributeType dt:type=“datatype” name=“name” required=“{yes | no }” />




The element Element

Refers to an element type declared earlier in the schema by using the ElementType element.

Is used to declare the content model for another element type.


<element type=“elementtype” minOccurs=“{0 | 1}” maxOccurs=“{1 | *}” />




The attribute Element

Refers to an attribute type declared earlier in the schema by using the AttributeType element.

Is used to declare the content model for another element type.


<attribute type=“attributetype” required=“{yes | no }” />



Task 3: Build a query.




Just a Minute…

The books sold at CyberShoppe are divided in to various categories, such as Science, Fiction, and Biography. The details about these books are stored in a SQL Server 2000 database. Create an XPath query for displaying the details about all fiction books. Also create a schema required for executing the query.



Problem Statement 9.D.3The branches of CyberShoppe send data about the sales made for various products in an XML document to the head office. On receiving this data, the head office needs to insert the details into a database table.



Task List

Identify the data that needs to be inserted.

Identify the method for inserting XML data into a database.

Build a query.

Execute the query.



Task 1: Identify the data that needs to be inserted.

Result

As per the scenario, the data that needs to be inserted into the SALES table is the sales details of the various products. The sales details includes the following:

ORDER

SHIP_ADD

PRICE_PER_QTY

QUANTITY



Task 2: Identify the method for inserting XML data into a database.

The OPENXML function is used to retrieve the data from an XML document as a rowset.

SQL Server 2000 provides the following system stored procedures that can be used with the OPENXML function.

sp_xml_preparedocument

sp_xml_removedocument

Result

You can use the OPENXML function with the sp_xml_preparedocument stored procedure to insert XML data into a database.



Task 3: Build a query.




Just a Minute…

What are the system stored procedures that can be used with the OPENXML function?



Summary

In this lesson, you learned that:

You can display data from a SQL Server 2000 database in a Web browser by using the SQL-XML integration feature.

To host a Web page, you need to install Internet Information Server (IIS) on a Windows 2000 or a Windows NT Server 4.0 system. If you have Windows NT Workstation 4.0 installed on a system, you can use Personal Web Server (PWS) instead of IIS.

The Virtual Directory Management option of SQL Server allows you to associate a SQL Server database with a virtual directory.



Summary (Contd.)

The FOR XML clause forms a part of the T-SQL statement in a URL query.

In a URL query, http://<servername>/<virtual-directoryname > should precede the SQL statement.

The white spaces in the SELECT statement of URL Query must be substituted by the ‘+’ sign.

An XPath query is an XML-based query language that can be used to process the data in XML documents.

Data can be inserted in SQL Server 2000 tables using the sp_xml_preparedocument stored procedure and OpenXML function.

Integrating XML with Microsoft SQL Server ©NIITeXtensible Markup Language/Lesson 9/Slide 1 of 31...

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