VB.Net/Database ADO.net/Table Relation
DataRelation: Create a relation between the two tables
<source lang="vbnet"> Imports System Imports System.Data Imports System.Windows.Forms Imports System.Data.SqlClient public class MainClass
Shared Sub Main() Dim form1 As Form = New Form1 Application.Run(form1) End Sub
End Class
Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New() MyBase.New() "This call is required by the Windows Form Designer. InitializeComponent() "Add any initialization after the InitializeComponent() call End Sub "Form overrides dispose to clean up the component list. Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean) If disposing Then If Not (components Is Nothing) Then components.Dispose() End If End If MyBase.Dispose(disposing) End Sub "Required by the Windows Form Designer Private components As System.ruponentModel.IContainer "NOTE: The following procedure is required by the Windows Form Designer "It can be modified using the Windows Form Designer. "Do not modify it using the code editor. Friend WithEvents DataGrid1 As System.Windows.Forms.DataGrid Friend WithEvents DataSet1 As System.Data.DataSet <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent() Me.DataGrid1 = New System.Windows.Forms.DataGrid Me.DataSet1 = New System.Data.DataSet CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).BeginInit() CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).BeginInit() Me.SuspendLayout() " "DataGrid1 " Me.DataGrid1.DataMember = "" Me.DataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText Me.DataGrid1.Location = New System.Drawing.Point(0, 0) Me.DataGrid1.Name = "DataGrid1" Me.DataGrid1.Size = New System.Drawing.Size(416, 224) Me.DataGrid1.TabIndex = 0 " "DataSet1 " Me.DataSet1.DataSetName = "NewDataSet" Me.DataSet1.Locale = New System.Globalization.CultureInfo("en-GB") " "Form1 " Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13) Me.ClientSize = New System.Drawing.Size(408, 221) Me.Controls.Add(Me.DataGrid1) Me.Name = "Form1" Me.Text = "Form1" CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).EndInit() CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).EndInit() Me.ResumeLayout(False) End Sub
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Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load "Create Connection object Dim thisConnection As New SqlConnection _ ("server=(local)\SQLEXPRESS;" & _ "integrated security=sspi;" & _ "database=MyDatabase") " Sql Queries Dim sql1 As String = _ "SELECT * FROM Employee; " Dim sql2 As String = _ "SELECT * FROM Employee" Dim sql As String = sql1 & sql2 " Create Data Adapter Dim da As New SqlDataAdapter(sql, thisConnection) " Map Default table names to Employees and Orders da.TableMappings.Add("Table", "Employee") da.TableMappings.Add("Table1", "Employee") " Fill Dataset da.Fill(DataSet1) " Create a relation between the two tables "Dim dr As New DataRelation( _ " "EmployeeOrder", _ " DataSet1.Tables(0).Columns("ID"), _ " DataSet1.Tables(1).Columns("ID")) "DataSet1.Relations.Add(dr) " Bind the data to the grid at runtime DataGrid1.SetDataBinding(DataSet1, "Employee") End Sub
End Class
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Define Table relation and load combined data into DataGrid
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Imports System Imports System.Drawing Imports System.Collections Imports System.ruponentModel Imports System.Windows.Forms Imports System.Data Imports System.Data.SqlClient
Public Class MainClass
Shared Sub Main( ) Application.Run(New ADOForm1() ) End Sub
End Class
Public Class ADOForm1 Inherits System.Windows.Forms.Form Friend WithEvents DataGrid1 As System.Windows.Forms.DataGrid Private components As System.ruponentModel.Container " private System.Data.ADO.ADOConnection myConnection; Private myConnection As System.Data.SqlClient.SqlConnection Private myDataSet As System.Data.DataSet Private myCommand As System.Data.SqlClient.SqlCommand Private myCommand2 As System.Data.SqlClient.SqlCommand Private myDataAdapter As System.Data.SqlClient.SqlDataAdapter Private myDataAdapter2 As System.Data.SqlClient.SqlDataAdapter Public Sub New( ) InitializeComponent( ) " create the connection object and open it Dim connectionString As String = _ "server=localhost; uid=sa; " & _ "pwd=YourPassword; database=northwind" myConnection = _ New System.Data.SqlClient.SqlConnection(connectionString) myConnection.Open( ) " create the DataSet and set a property myDataSet = New System.Data.DataSet( ) myDataSet.CaseSensitive = True " create the SqlCommand object and assign the " connection and the select statement myCommand = New System.Data.SqlClient.SqlCommand( ) myCommand.Connection = myConnection myCommand.rumandText = "Select * from Employees" myCommand2 = New System.Data.SqlClient.SqlCommand( ) myCommand2.Connection = myConnection myCommand2.rumandText = "Select * from Orders" " create the myDataAdapter object and pass in the " SQL Command object and establish the table mappings myDataAdapter = New System.Data.SqlClient.SqlDataAdapter( ) myDataAdapter2 = New System.Data.SqlClient.SqlDataAdapter( ) myDataAdapter.SelectCommand = myCommand myDataAdapter2.SelectCommand = myCommand2 myDataAdapter.TableMappings.Add("Table", "Employees") myDataAdapter2.TableMappings.Add("Table", "Orders") " Tell the myDataAdapter object to fill the DataSet myDataAdapter.Fill(myDataSet) myDataAdapter2.Fill(myDataSet) Dim myDataRelation As System.Data.DataRelation Dim dataColumn1 As System.Data.DataColumn Dim dataColumn2 As System.Data.DataColumn dataColumn1 = _ myDataSet.Tables("Employees").Columns("EmployeeID") dataColumn2 = _ myDataSet.Tables("Orders").Columns("EmployeeID") myDataRelation = New System.Data.DataRelation( _ "EmployeesToOrders", dataColumn1, dataColumn2) myDataSet.Relations.Add(myDataRelation) Dim dataSetView As DataViewManager = _ myDataSet.DefaultViewManager " display it in the grid DataGrid1.DataSource = _ dataSetView DataGrid1.DataMember = "Employees" End Sub "New Private Sub InitializeComponent( ) Me.ruponents = New System.ruponentModel.Container( ) Me.dataGrid1 = New System.Windows.Forms.DataGrid( ) dataGrid1.Location = New System.Drawing.Point(48, 24) dataGrid1.Size = New System.Drawing.Size(368, 160) dataGrid1.TabIndex = 0 Me.Text = "ADOFrm1" Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13) Me.ClientSize = New System.Drawing.Size(464, 273) Me.Controls.Add(dataGrid1) End Sub End Class </source>
<source lang="vbnet"> Imports System.Data.SqlClient Imports System.Windows.Forms <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Class Relation
Inherits System.Windows.Forms.Form <System.Diagnostics.DebuggerStepThrough()> _ Private Sub InitializeComponent() Me.cmdClear = New System.Windows.Forms.Button Me.cmdFill = New System.Windows.Forms.Button Me.lstOrder = New System.Windows.Forms.ListBox Me.SuspendLayout() " "cmdClear " Me.cmdClear.Anchor = CType((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles) Me.cmdClear.Location = New System.Drawing.Point(210, 238) Me.cmdClear.Name = "cmdClear" Me.cmdClear.Size = New System.Drawing.Size(72, 24) Me.cmdClear.TabIndex = 5 Me.cmdClear.Text = "Clear" " "cmdFill " Me.cmdFill.Anchor = CType((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Left), System.Windows.Forms.AnchorStyles) Me.cmdFill.Location = New System.Drawing.Point(10, 238) Me.cmdFill.Name = "cmdFill" Me.cmdFill.Size = New System.Drawing.Size(72, 24) Me.cmdFill.TabIndex = 4 Me.cmdFill.Text = "Fill" " "lstOrder " Me.lstOrder.Anchor = CType((((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom) _ Or System.Windows.Forms.AnchorStyles.Left) _ Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles) Me.lstOrder.IntegralHeight = False Me.lstOrder.Location = New System.Drawing.Point(10, 3) Me.lstOrder.Name = "lstOrder" Me.lstOrder.Size = New System.Drawing.Size(272, 229) Me.lstOrder.TabIndex = 3 " "Relation " Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!) Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font Me.ClientSize = New System.Drawing.Size(292, 267) Me.Controls.Add(Me.cmdClear) Me.Controls.Add(Me.cmdFill) Me.Controls.Add(Me.lstOrder) Me.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte)) Me.Name = "Relation" Me.Text = "Relation" Me.ResumeLayout(False) End Sub Friend WithEvents cmdClear As System.Windows.Forms.Button Friend WithEvents cmdFill As System.Windows.Forms.Button Friend WithEvents lstOrder As System.Windows.Forms.ListBox Private Sub cmdFill_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdFill.Click Dim Connect As String = "Data Source=localhost;Integrated Security=True;Initial Catalog=Northwind;" Dim con As New SqlConnection(Connect) Dim SQL As String = "SELECT * FROM Orders " Dim cmd As New SqlCommand(SQL, con) Dim adapter As New SqlDataAdapter(cmd) Dim dsNorthwind As New DataSet() con.Open() adapter.Fill(dsNorthwind, "Orders") cmd.rumandText = "SELECT * FROM Customers" adapter.Fill(dsNorthwind, "Customers") cmd.rumandText = "SELECT * FROM Employees" adapter.Fill(dsNorthwind, "Employees") con.Close() Dim relCustomersOrders As New DataRelation("CustomersOrders", _ dsNorthwind.Tables("Customers").Columns("CustomerID"), _ dsNorthwind.Tables("Orders").Columns("CustomerID")) dsNorthwind.Relations.Add(relCustomersOrders) Dim rowParent, rowChild As DataRow For Each rowParent In dsNorthwind.Tables("Customers").Rows For Each rowChild In rowParent.GetChildRows(relCustomersOrders) lstOrder.Items.Add(rowParent("CompanyName") & _ " ordered on " & rowChild("OrderDate")) Next Next End Sub Private Sub cmdClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdClear.Click lstOrder.Items.Clear() End Sub
End Class
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