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IT 390 Business Database Administration Unit 9: Database Access Standards © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 1 Objectives • Identify and classify ODBC, OLE DB, and ASP standards. Introduce database access standards. Explain ODBC, OLE DB and ASP standards. • Define and apply basic XML and ADO .NET • Explain XML and ADO.NET © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 2 ODBC Introduction • You need interfaces to enable applications interact and exchange data with databases. • ODBC is a Microsoft specification for creating a database application programming interface (API). The ODBC API is implemented in the form of drivers. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 3 More about ODBC • The ODBC works as an interface between an RDBMS and Application Program. This setup works in a three-tier architecture. • SQL Server 2000 connects to development modules using specific API drivers. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 4 ODBC Architecture • The components of ODBC architecture enable the ODBC API to communicate with a database. These components interact with each other to make the database accessible to the user. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 5 ODBC Visual Overview API ODBC SQL Server 2000 ODBC API © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 6 Functions of ODBC • Enables applications to communicate with different databases • Facilitates SQL grammar conversion • Enables a single application to use different drivers • Enables applications to interact with different types of databases • Allows the use of enhanced DBMS features • Enables applications to achieve a three-layered architecture © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 7 Components of ODBC There are four components of the ODBC architecture that interact with each other to to make the required output available to the user. • Application: Applications are the programs that call the ODBC API to communicate with the DBMS. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 8 Components of ODBC Driver manager: It is the component that enables communication between an application and a driver by monitoring the transactions between them. A driver manager also performs basic errorhandling tasks after a connection is established between the application and the driver. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 9 Components of ODBC (cont.) • Drivers: Drivers are software components that provide functions in the ODBC API. • Data source: A data source stores all the information that is necessary to connect to a database or a DBMS that is stored on the same computer as the client computer or on another computer on the network. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 10 ODBC is NOT Microsoft exclusively © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 11 Setting Up an ODBC Data Source • You use the ODBC Data Source Administrator dialog box to create a DSN. The ODBC Data Source Administrator function is available in Control Panel in the Windows 98 operating system. In Windows 2000, the ODBC Data Source Administrator function is available under Administrative Tools. • To set up an ODBC Data Source: Double-click the Data Sources icon in the Control Panel. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 12 Setting Up an ODBC Data Source (cont.) Then, on the ODBC Data Source Administrator screen, click the System DSN tab. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 13 Setting Up an ODBC Data Source (cont.) In the System DSN tabbed page, click the Add button. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 14 Setting Up an ODBC Data Source (cont.) Clicking the Add button displays the Create New Data Source dialog box. In this dialog box, select the SQL Server option, and click the Finish button. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 15 Setting Up an ODBC Data Source (cont.) The Create a New Data Source to SQL Server wizard appears. In the first screen of the Create New Data Source Wizard, specify the name for a data source, a description for the data source, and the name of the SQL Server that you want the DSN to connect. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 16 Setting Up an ODBC Data Source (cont.) On the next screen, click the With SQL Server authentication using a login ID and password entered by the user option. Then, specify a login ID and password. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 17 Setting Up an ODBC Data Source (cont.) After specifying the login ID and password for SQL authentication, select the Change the default database to option, and select the name of the database from the drop-down list. Accept the default selections for other options, and then click the Next button. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 18 Setting Up an ODBC Data Source (cont.) On the next screen of the wizard, accept all the default selections, and then click the Finish button. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 19 Setting Up an ODBC Data Source (cont.) You can see the data source name included in the list of other data sources on the System DSN tabbed page. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 20 Using an ODBC Data Source To connect to the database, you need a front-end application. In addition, you need to call the following functions in the code of the front-end application. 1. Call the SQLAllocEnv or SQLAllocHandle function to get an environment handle. 2. Call the SQLAllocConnect function. 3. Call the SQLConnect function. 4. Call the SQLExecDirect function to execute the SQL statements. 5. Call the SQLFreestmt function to close the connection. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 21 State whether True or False • The functions of ODBC are: 1) Enables applications to communicate with only SQL Server 2000. 2) Enables a single application to use different drivers. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 22 Solution (True or False) 1) False 2) True © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 23 Class Activity • Choose the correct ODBC components from the following list: Application File system Driver manager Driver Operating system Data source © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 24 Solution • • • • Application Driver manager Driver Data source © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 25 OLE DB and its Components • OLE DB consists of three components: Data providers Data consumers Service components © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 26 © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 27 © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 28 •An ADO object model uses object-oriented programming techniques to communicate with the underlying data source. ADO creates a layer between the applications and the OLE DB provider. • The ADO object model consists of nine objects and four collections. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 29 The ADO Object Model (cont.) The nine objects are: • Connection • Error • Command • Recordset • Record • Parameter • Field • Property • Stream © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 30 The ADO Object Model (cont.) The four collections are: • Fields • Properties • Parameters • Errors © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 31 Accessing Databases by Using ADO The generic steps to access databases using ADO are: 1. Set up reference to an ADO Connection object. 2. Define the connection string to be used when opening the connection object. The connection string can be defined in two ways, with a DSN or without a DSN. 3. Open the connection object by using the Open method of the connection object. 4. Use the state property of the connection object to check whether or not a connection is established successfully. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 32 Accessing Databases Using ADO (cont.) 5. Execute SQL statements after the connection is established. 6. Create a recordset object and execute it by using the Open method of the recordset object. 7. Close the recordset object. In addition, close the connection object by calling the Close method of the connection object. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 33 Active Data Objects (ADO) • Active Data Objects (ADO) characteristics: A simple object model for OLE DB data consumers. It can be used from VBScript, JScript, Visual Basic, Java, C#, C++. It is a single Microsoft data access standard. Data access objects are the same for all types of OLE DB data. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 34 Invoking ADO from Active Server Pages • In Microsoft’s Active Server Pages (ASP) are Web pages where: Statements are enclosed within the characters <% . . .%>. ASP statements are processed on the Web server. Other (HTML) statements are processed by the client Web browser. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 35 The ADO Object Model © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 36 Connection Object • A connection object establishes a connection to a data provider and data source. Connections have an isolation mode. • Once a connection is created, it can be used to create RecordSet and Command objects. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 37 RecordSet Objects RecordSet objects represent cursors: They have both CursorType and LockType properties. RecordSets can be created with SQL statements. The Fields collection of a RecordSet can be processed to individually manipulate fields. The Errors collection contains one or more error messages that result from an ADO operation. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 38 Command Object The command object is used to execute stored parameterized queries or stored procedures: Input data can be sent to the correct ASP using the HTML FORM tag. Table updates are made using the RecordSet Update method. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 39 ADO Constants: Isolation Levels © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 40 ADO Constants: Cursor Levels © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 41 ADO Constants: Lock Types © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 42 Connection Object: ASP Code <% Dim objConn Set objConn = Server.CreateObject (“ADODB.connection”) objConn.IsolationLevel = adXactReadCommitted ‘ use ADOVBS objConn.Open “ViewRidgeSS”, %> <!--#include virtual =“ADOExamples/ADOVBS.inc --> <% objConn.Open “DSN=ViewRidgeOracle2;UID=DK1;PWD=Ses ame” %> © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 43 RecordSet Object: ASP Code <% Dim objRecordSet, varSql varSQL = “SELECT * FROM ARTIST” Set objRecordSet = Server.CreateObject(“ADODB.Recordset ”) objRecordSet.CursorTye = adOpenStatic objRecordSet.LockType = adLockReadOnly objRecordSet.Open varSQL, objConn %> © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 44 Fields Collection: ASP Code <% Dim varI, varNumCols, objField varNumCols = objRecordSet.Fields.Count For varI = 0 to varNumCols - 1 Set objField = objRecordSet.Fields(varI) ‘ objField.Name now has the name of the field ‘ objField.Value now has the value of the field ‘ can do something with them here Next >% © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 45 Errors Collection: ASP Code <% Dim varI, varErrorCount, objError On Error Resume Next varErrorCount = objConn.Errors.Count If varErrorCount > 0 Then For varI = 0 to varErrorCount - 1 Set objError = objConn.Errors(varI) ‘ objError.Description contains ‘ a description of the error Next End If >% © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 46 Command Object: ASP Code <% Dim objCommand, objParam, objRs ‘Create the Command object, connect it to objConn and set its format Set objCommand = Server.CreateObject(“ADODB.command”) Set objCommand.ActiveConnection = objConn objCommand.CommandText=“{call FindArtist (?)}” ‘Set up the parameter with the necessary value Set objParam = objCommand.CreateParameter (“Nationality”, adChar, adParamInput, 25) objCommand.Parameters.Append objParam objParam.Value = “Spanish” ‘Fire the Stored Proc Set objRs = objCommand.Execute >% © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 47 ADO Example: Reading a Table Artist.asp © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 48 ADO Example: Reading a Table The Artist.asp Results © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 49 Class Activity • Identify the objects in the ADO Model: Connection Error Recordset File Attribute Stream © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 50 Solution • • • • Connection Error Recordset Stream © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 51 Accessing Databases by Using XML • XML provides a way to define meaningful data structures and eases the process of data exchange. • The advantages of using XML are: Provides extensible tags to define applicationspecific data structures Enables the creation of platform-independent application Requires only updated document to be uploaded on the Internet instead of the complete document Displays the same information in different formats on the Web © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 52 More about XML • Provides extensible tags for defining application-specific data structures. • Enables the creation of platform-independent applications. • Helps reduce the Internet traffic. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 53 © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 54 XML Documents • XML can be used to present any kind of information in a simple, structured format. The following are the parts of an XML document: An XML document begins with a <?xml version =“1.0”?> declaration tag. The second component in an XML document is called an element. An element is referred to as a root element, when it describes the details about all other elements. Below the root element, there is a hierarchy of elements. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 55 XML Documents (cont.) All the elements in an XML document contain some data. The data is called content. • When you create an XML document, you need to follow certain rules. These rules are: Every start tag should have a closing tag called the end tag. Tags should not overlap because XML documents follow a hierarchy. There can be only one root element. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 56 XML for Data Exchange • The architecture of an application has three layers. The business layer The data layer The user interface • These layers communicate with each other and exchange data to perform the functions required in an application. • In this entire process of data exchange, XML is used extensively at each stage. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 57 SQL Server 2000 and Relational Data in XML • SQL Server 2000 provides the OPENXML function to insert and update records in the database from an XML document. The OPENXML function reads the data from an XML document and inserts it into the database. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 58 Integrating XML with SQL Server 2000 • SQL server 2000 is an XML-enabled RDBMS that retrieves data from an SQL database and presents it as XML data. To retrieve data, you need to use the FOR XML clause in the SELECT statement. • To get the XML output for a SQL query, an additional clause is added at the end of the SQL statement: [FOR XML {RAW|AUTO|EXPLICIT} [, XMLDATA] [, ELEMENTS] [, BINARY base64]] • The FOR XML clause has three distinct options: RAW, AUTO, and EXPLICIT. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 59 Inserting and Updating Relational Data from XML Data • SQL Server 2000 provides the OPENXML function to insert and update records in a database from an XML document. • To insert and update records, the OPENXML function uses two system stored procedures: sp_xml_preparedocument sp_xml_removedocument © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 60 Class Activity • Identify the error in the following XML code displaying the employee name: <?xml version ="1.0"?> <EmployeeInfo> <Employee ID="001"> <EmployeeName> Joe </EmployeeInfo> © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 61 Solution • The correct code is: <?xml version ="1.0"?> <EmployeeInfo> <Employee ID="001"> <EmployeeName> Joe </EmployeeName> /*the closing tag was missing*/ </EmployeeInfo> © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 62 Rules for Creating an XML Document • Start tag has a closing tag called the end tag. • Tags should not overlap because an XML document follows a hierarchy. • There can be only one root element. • XML is a case-sensitive language. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 63 Class Activity • Identify the various XML formatting options: RAW 2) AUTO 3) TEXTSPACE 4) EXPLICIT 5) NAME 1) © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 64 Solution • RAW • AUTO • EXPLICIT © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 65 Summary • ODBC is a specification for creating a database API. • There are four main components of ODBC: Application Driver Manager Driver Data Source • You use the ODBC Data Source Administrator dialog box to create a DSN. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 66 Summary • OLE DB and ADO provide a common method to access data from different data sources. • OLE DB has three components: Data provider Data consumers Service components © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 67 Summary • The ADO object model consists of the following nine objects: Connection Error Command Recordset Record Parameter Field Property Stream © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 68 Summary • The steps to access database using ADO are: 1. 2. 3. 4. 5. 6. 7. Set up reference to an ADO Connection object. Define the connection string to be used. Open the connection object. Use the state property to check the establishment of the connection. Execute SQL statements. Create a recordset object. Close the recordset object and the connection object. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 69 Summary • • XML is a standard that can present structured data in the text format on the Web. Parts of an XML document: Declaration statement Tags Elements © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 70 Summary • You use the FOR XML clause in the SELECT statement to integrate XML with SQL Server. • The FOR XML clause has three distinct options: RAW AUTO EXPLICIT • SQL Server 2000 provides an OPENXML function to insert and update records in a database from an XML document. © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 71 Summary Did you understand the key points from the Lesson? Do you have any questions?? © 2006 ITT Educational Services Inc. Course Name: IT390 Business Database Administration Unit 9 Slide 72