This document provides an overview and lessons for Module 10 on accessing data with Microsoft ADO.NET. It covers topics like connecting to databases, using datasets and datareaders to access and display data, handling relationships between multiple tables, and best practices for organizing ADO.NET code. The lessons include tutorials, demonstrations, and practices for students to reinforce the concepts.

1. Module 10: Accessing Data with Microsoft ADO.NET

2. Overview Introduction to Using ADO.NET Connecting to a Database Accessing Data with DataSets Using Multiple Tables Accessing Data with DataReaders

3. Lesson: Introduction to Using ADO.NET Multimedia: The ADO.NET Object Model Using DataSets vs. DataReaders Practice: When to Use DataSets or DataReaders

4. Multimedia: The ADO.NET Object Model

5. Using DataSets vs. DataReaders Supported by Visual Studio .NET tools Slower access Forward-only Bind to one control only Based on one SQL statement from one database Read-only Manually coded Faster access Forward and backward scanning of data Bind to multiple controls Includes multiple tables from different databases Read/write access to data DataReader DataSet Disconnected Connected

6. Practice: When to Use DataSets or DataReaders Students will: Select the best data access choice for given scenarios Time: 5 Minutes

7. Lesson: Connecting to a Database SQL Server Security Creating the Connection Demonstration: Setting SQL Server Security

8. SQL Server Security Client Send the username and password in clear text. Do not send the username and password. Just send that the user has been authenticated. Mixed mode authentication Windows only authentication SQL Server Only ASPNET account is granted access Web Server Windows authentication or… SQL Server Each user account added to SQL Server logins group Web Server Default ASP.NET settings Here is the username and password

9. Creating the Connection Using SqlConnection Setting connection string parameters Connection timeout Data source Initial catalog Integrated security Dim strConn As String = "data source=localhost; " & _ "initial catalog=northwind; integrated security=true" Dim conn As New SqlConnection(strConn) Password Persist security info Provider User ID string strConn = "data source=localhost; " + "initial catalog=northwind; integrated security=true"; SqlConnection conn = new SqlConnection(strConn);

10. Demonstration: Setting SQL Server Security Open SQL Server Enterprise Manager Set authentication mode Test with integrated security Test with mixed mode security

11. Lesson: Accessing Data with DataSets Creating a DataAdapter Creating a DataSet Demonstration: Programmatically Using a DataSet Using a DataView Practice: Organizing Code to Create a DataSet Binding a DataSet to a List-Bound Control Instructor-Led Practice: Displaying a DataSet Handling Errors

12. Creating a DataAdapter Store the query in a DataAdapter The DataAdapter constructor sets the SelectCommand property Set the InsertCommand, UpdateCommand, and DeleteCommand properties if needed Dim da As New SqlDataAdapter _ ("select * from Authors", conn) da.SelectCommand.CommandText da.SelectCommand.Connection SqlDataAdapter da = new SqlDataAdapter ("select * from Authors",conn); da.SelectCommand.CommandText; da.SelectCommand.Connection;

13. Creating a DataSet Create and populate a DataSet with DataTables Fill method executes the SelectCommand Access a DataTable Dim ds As New DataSet() da.Fill(ds, "Authors") Dim r As DataRow Dim str As String For Each r in _ ds.Tables("Authors").Rows str &= r(2) str &= r("au_lname") Next ds.Tables("Authors").Rows.Count DataSet ds = new DataSet(); da.Fill(ds, "Authors"); ds.Tables["Authors"].Rows.Count; string str=""; foreach(DataRow r in ds.Tables["Authors"].Rows) { str += r[2]; str += r["au_lname"]; }

14. Demonstration: Programmatically Using a DataSet Create a Connection Create DataAdapter Create DataSet Read data from DataSet programmatically

15. Using a DataView A DataView can be customized to present a subset of data from a DataTable The DefaultView property returns the default DataView of the table Setting up a different view of a DataSet DataView dv = new DataView(ds.Tables["Authors"]); dv.RowFilter = "state = 'CA'"; Dim dv As DataView = ds.Tables("Authors").DefaultView Dim dv As New DataView (ds.Tables("Authors")) dv.RowFilter = "state = 'CA'" DataView dv = ds.Tables["Authors"].DefaultView;

16. Practice: Organizing Code to Create a DataSet Student will: Reorder lines of code to create a DataSet Time: 5 Minutes

17. Binding a DataSet to a List-Bound Control Create the control Bind to a DataSet or a DataView dg.DataSource = ds dg.DataMember = &quot;Authors&quot; dg.DataBind() <asp:DataGrid id=&quot;dg&quot; runat=&quot;server&quot; /> dg.DataSource = ds; dg.DataMember = &quot;Authors&quot;; dg.DataBind() ;

18. Instructor-Led Practice: Displaying a DataSet Create a Connection Create a DataAdapter Create a DataSet Create a DataView Bind both the DataSet and DataView to DataGrid controls

19. Handling Errors Connection will not open Connection string is invalid Server or database not found Login failed DataAdapter cannot create a DataSet Invalid SQL syntax Invalid table or field name Code Example

20. Lesson: Using Multiple Tables Storing Multiple Tables Creating Relationships Programmatically Navigating Between Tables Using Relationships Visually Navigating Between Tables Using Relationships Instructor-Led Practice: Displaying Data from Multiple Tables

21. Storing Multiple Tables Add the first table Add the subsequent table(s) daCustomers = New SqlDataAdapter _ (&quot;select * from Customers&quot;, conn1) daCustomers.Fill(ds, &quot;Customers&quot;) Orders Customers daOrders = New SqlDataAdapter _ (&quot;select * from Orders&quot;, conn2) daOrders.Fill(ds, &quot;Orders&quot;) conn2 conn1 DataSet

22. Creating Relationships Identify parent column Identify child column Create DataRelation Dim dr As New DataRelation _ (&quot;name&quot;, parentCol, _ childCol) ds.DataRelations.Add(dr) Dim parentCol As DataColumn = _ ds.Tables(&quot;Customers&quot;).Columns(&quot;CustomerID&quot;) Dim childCol As DataColumn = _ ds.Tables(&quot;Orders&quot;).Columns(&quot;CustomerID&quot;) Orders table Customers table DataSet parentCol childCol DataRelation C# Code Example

23. Programmatically Navigating Between Tables Using Relationships ds.Tables( index ).Rows( index ).GetChildRows(&quot; relation &quot;) ds.Tables( index ).Rows( index ).GetParentRow(&quot; relation &quot;) Customers Orders GetChildRows GetParentRow DataSet ds.Tables[ index ].Rows[ index] .GetChildRows(&quot; relation &quot;); ds.Tables[ index] .Rows[ index] .GetParentRow(&quot; relation &quot;);

24. Visually Navigating Between Tables Using Relationships Dim tableView As DataView Dim currentRowView As DataRowView tableView = New DataView(ds.Tables(&quot;Customers&quot;)) currentRowView = tableView(dgCustomers.SelectedIndex) dgChild.DataSource = currentRowView.CreateChildView(&quot;CustOrders&quot;) Customers Orders CreateChildView DataRowView DataView DataSet DataView tableView; DataRowView currentRowView; tableView = new DataView(ds.Tables[&quot;Customers&quot;]); currentRowView = tableView[dgCustomers.SelectedIndex]; dgChild.DataSource = currentRowView.CreateChildView(&quot;CustOrders&quot;);

25. Instructor-Led Practice: Displaying Data from Multiple Tables Programmatically: Create a DataSet Create a DataRelation Display child records using the DataRelation Visually: Call CreateChildView

26. Lesson: Accessing Data with DataReaders What is a DataReader? Creating a DataReader Reading Data from a DataReader Binding a DataReader to a List-Bound Control Practice: Organizing Code to Create a DataReader Demonstration: Displaying Data Using DataReaders

27. What is a DataReader? Forward-only, read-only Fast access to data Connected to a data source Manage the connection yourself Manage the data yourself, or bind it to a list-bound control Uses fewer server resources

28. Creating a DataReader To use a DataReader: Create and open the database connection Create a Command object Create a DataReader from the Command object Call the ExecuteReader method Use the DataReader object Close the DataReader object Close the Connection object Use Try…Catch…Finally error handling Code Example 1 2 3 4 5 6 7

29. Reading Data from a DataReader Call Read for each record Returns false when there are no more records Access fields Parameter is the ordinal position or name of the field Get functions give best performance Close the DataReader Close the connection Do While myReader.Read() str &= myReader(1) str &= myReader(&quot;field&quot;) str &= myReader.GetDateTime(2) Loop while (myReader.Read()) { str += myReader[1]; str += myReader[&quot;field&quot;]; str += myReader.GetDateTime(2); }

30. Binding a DataReader to a List-Bound Control Create the Control Bind to a DataReader dgAuthors.DataSource = dr dgAuthors.DataBind() <asp:DataGrid id=&quot;dgAuthors&quot; runat=&quot;server&quot; /> dgAuthors.DataSource = dr; dgAuthors.DataBind();

31. Practice: Organizing Code to Create a DataReader Students will: Reorder lines of code to create a DataReader Time: 5 Minutes

32. Demonstration: Displaying Data Using DataReaders Create a SqlConnection Create a DataReader Bind the DataReader to a ListBox Build ListBox items from data supplied by the DataReader

33. Review Introduction to Using ADO.NET Connecting to a Database Accessing Data with DataSets Using Multiple Tables Accessing Data with DataReaders

34. Lab 10: Accessing Data with Microsoft ADO.NET Medical Medical.aspx Benefits Home Page Default.aspx Life Insurance Life.aspx Retirement Retirement.aspx Dental Dental.aspx Dentists Doctors Doctors.aspx Doctors Logon Page Login.aspx Registration Register.aspx Coho Winery Prospectus Prospectus.aspx XML Web Service dentalService1.asmx Page Header Header.ascx ASPState tempdb Lab Web Application User Control namedate.ascx Menu Component Class1.vb or Class1.cs XML Files Web. config