DAT304

Leveraging XML and HTTP with Sql Server

Irwin DolobowskyProgram ManagerWebdata Group

Agenda

SQLXML Overview

Data Access Methods

FOR XML Queries over HTTP

XPath Queries over HTTP

Binary Data

Xml Templates & Updategrams

Web Servies

Demos

Configuring SQL Server to work over HTTP (virtual directories)

Executing Sql queries over HTTP

Executing XPath queries over HTTP

Xml Templates & Updategrams

SQLXML Web Services

The Two Worlds

SQLSQLServerServer

RowSetRowSet

SQLSQL

Relational Relational worldworld

LanguageLanguage

Data Data storagestorage

Data Data outputoutput

XML XML worldworld

XMLXMLFilesFiles

XPathXPathXQueryXQuery

XML/XML/HTMLHTML

XMLXMLViewView

SQLXML SQLXML – –

Bringing Bringing worlds worlds

togethertogether

Query/Update Technologies

FOR XML (raw, auto, nested, explicit)SQL language extension to retrieve XML instead of rowsets

XML Views – XPathWork with your relational database as if it was XML file (through annotated schema)

Updategrams/DiffgramsUpdate through XML View

BulkloadShred large XML files into existing tables

Data Access Methods

HTTP Access via URLSQL Query

XPath Query

XML Templates

DBObjects

Web services with SQL Virtual Directories

ADO / OLEDB

.NET access through SQLXML Managed Classes or ADO.NET

Custom Web Services

HTTP access to SqlXml

Easy as setting up a virtual directory

Can query directly with query strings

Best practices:Use templates for abstraction

No blank sa passwords!

Create the physical directory first

Steps: Configure XML support in IIS for

SQL Server Launch Click the Start button and select Programs Microsoft SQL Server Configure SQL XML Support In IIS

Create a new virtual directory

Set physical path

Configure connection security

Choose data source

Steps: Configure XML support in IIS for

SQL Server Configure access settings

Allow URL Queries

Allow Template Queries (*Default)

Allow XPath

Other tabs…Virtual Names (you will see this later)

Advanced

Configuring XML support in IIS for Sql Server

Irwin Dolobowsky

Program Manager

Webdata Group

demodemo

Construct a simple HTTP Query

SELECT * from Customers FOR XML AUTO

Convert it to an HTTP request, by concatenating it with plus-sign (+) delimiters into:

SELECT+*+FROM+CUSTOMERS+FOR+XML+AUTO

Append that onto the URL for the virtual directory that you’ve created, by using the sql querystring parameter

http://localhost/NorthwindCustomers?sql= SELECT+*+FROM+CUSTOMERS+FOR+XML+AUTO

Execute SQL Queries over HTTP

Irwin Dolobowsky

Program Manager

Webdata Group

demodemo

XPath queries over HTTPUse XPath to query SQL Database as if it was an XML fileQuery over Xml View

Mapping XSD to Relational SchemaMuch easier that FOR XML EXPLICITAbstract away Database

StepsCreate annotated XSD (mapping/Xml View)Configure the virtual Schema directoryQuery against AXSD with XPath over HTTP

Execute XPath Queries Execute XPath Queries over HTTPover HTTP

Irwin Dolobowsky

Program Manager

Webdata Group

demodemo

Using DbObjectsEnables you to return BLOBsEach query translates into a SQL statementQuery returning a character column

http://localhost/demos/dbobject/Employees[@EmployeeID=1]/@LastName

Query returning a blob columnhttp://

localhost/demos/dbobject/Employees[@EmployeeID=1]/@Photo

Query using parametershttp://localhost/demos/dbobject/

Employees[@EmployeeID=$eid]/@Photo?eid=1

Working with Binary Large Objects

Irwin Dolobowsky

Program Manager

Webdata Group

demodemo

Working with BLOBs

TechniquesBase64

DBObject

How to decide?Do you have access to the pointer (location) from DBObject?

DBObject faster

Xml Templates

XmlDocument with embedded queriesFOR XML QueriesXPath over Annotated XSD

When template is executed, query results are filled in

Dynamic XML documentParameterizedUse templates over raw URL queries

Get cachingEncapsulationSecurityControl

Steps: XML Templates over HTTP

Enable virtual directory settings Create query in template format

<sql:query></sql:query>Create the physical template directoryConfigure the virtual template mappingSave into XML file in template directoryJust point to the template with a URL

Using sql:query

<NWCustomers xmlns:sql="urn:schemas-microsoft-com:xml-sql">

<sql:query> SELECT CustomerID,

CompanyName, City, Country

FROM Customers FOR XML AUTO, ELEMENTS </sql:query></NWCustomers>

Updategrams & XML ViewsModify the database through the XML ViewDeclare before and after images of the XML (what it is now, and what you want it to be)Optimistic concurrency control ensures that the transaction takes place only if the before image matches the current database stateEach updategram is translated into one or more INSERT, UPDATE, and DELETE statements, carried out as a single transaction

Updategrams And XMLViews<updategram-example> <updg:sync mapping-schema=“schema.xsd”

xmlns:updg=“urn:schemas-microsoft-com:xml-updategram”>

<updg:before> <Customer CustomerID=“LAZYK” Address=“12 Orchestra

Terrace”> <Order OrderID=“27” UnitPrice=“100” Quantity=“1000” /> </Customer></updg:before>

<updg:after> <Customer CustomerID=“LAZYK” Address=“8 Opera Court”/></updg:after>

</updg:sync></updategram-example>

XML Templates & Updategrams: Tying it all togetherIrwin Dolobowsky

Program Manager

Webdata Group

demodemo

Web Services Overview

Web Services expose Stored Procedures and XML Templates

Messaging done according to SOAP 1.1 standard

Variety of response options

Can run on database server or mid-tierWherever IIS is

Simple UI for configurationEven DBA’s can do it!

What Does SQLXML Do For You?

Creates Web Services Description Language (WSDL) file

Describes Web Service

Indicates what Methods are available

Difficult to write by hand. WE DO IT FOR YOU!

Parse SOAP requests

Return proper SOAP response

Creating A Web Service

Use the configuration tool to create a Virtual Directory (VDir)

Create a Virtual Name of type “SOAP”Name your Web Service

Give it a domain

You Have a Web Service!You Have a Web Service!

Now to add some methods…Now to add some methods…

XML Template Methods

Browse for an XML Template

Choose Web Method name

Results always returned in “XML Objects” mode

Stored Procedure Methods

Select Stored Procedure from listGenerated from login used for the VDir

Choose Web Method name

Select Output Formatting RAW or NESTED

Select Response Type XML Objects

Dataset Objects

Single Dataset

Visual Studio.NET Integration

SQLXML 3.0 Web Services designed for Visual Studio.NET

In a Visual Studio.NET Project, “Add Web Reference” to your Web Service

Proxy classes generated for your methods

Forget that you are not accessing local information

Visual Studio.NET takes care of the SOAP messaging and XML serialization / de-serialization for you

Exposing and AccessingExposing and AccessingSProcs as Web ServicesSProcs as Web Services

Irwin Dolobowsky

Program Manager

Webdata Group

demodemo

Response Types

All Responses are XML / SOAPResponse Type dictates what Visual Studio.NET De-Serializes the XML into

Other clients will just see XML

Single Dataset Response Limitations

No Error InformationEither a dataset comes back or it doesn’t, no other messages

Single Result Sets OnlyUse Dataset Objects mode instead

Community Resources

Main web page and download SQLXML releases at:

http://msdn.microsoft.com/sqlxml/

Contactsnews:microsoft.public.sqlserver.xmlEmail me: irwind@microsoft.com

DocumentationSQL Server 2000 Documentation (Books Online)Web Release documentationBooks

Community Resources

Community Resourceshttp://www.microsoft.com/communities/default.mspx

Most Valuable Professional (MVP)http://www.mvp.support.microsoft.com/

NewsgroupsConverse online with Microsoft Newsgroups, including Worldwidehttp://www.microsoft.com/communities/newsgroups/default.mspx

User GroupsMeet and learn with your peershttp://www.microsoft.com/communities/usergroups/default.mspx

Ask The ExpertsGet Your Questions Answered

After this talk

ATE – Now – 14:00

evaluationsevaluations

© 2003 Microsoft Corporation. All rights reserved.© 2003 Microsoft Corporation. All rights reserved.This presentation is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS SUMMARY.This presentation is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS SUMMARY.