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Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Data.OleDb
Imports System.Data.Common
Imports System.Data
Public Class MainClass
Shared Sub Main()
Dim dsUsers As New DataSet("Employee")
Try
' Define a connection object
Dim dbConn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Password=;User ID=Admin;Data Source=Employee.mdb")
' Create a data adapter to retrieve records from db
Dim daUsers As New OleDbDataAdapter("SELECT ID, FirstName, LastName FROM Employee", dbConn)
' Define each column to map
Dim dcmUserID As New DataColumnMapping("ID", "EmployeeID")
Dim dcmFirstName As New DataColumnMapping("FirstName", "FirstName")
Dim dcmLastName As New DataColumnMapping("LastName", "LastName")
' Define the table containing the mapped columns
Dim dtmUsers As New DataTableMapping("Table", "Employee")
dtmUsers.ColumnMappings.Add(dcmUserID)
dtmUsers.ColumnMappings.Add(dcmFirstName)
dtmUsers.ColumnMappings.Add(dcmLastName)
' Activate the mapping mechanism
daUsers.TableMappings.Add(dtmUsers)
' Fill the dataset
daUsers.Fill(dsUsers)
' Set the primary key in order to use the Find() method
' below.
Dim dcaKey() As DataColumn = {dsUsers.Tables(0).Columns("EmployeeID")}
dsUsers.Tables(0).PrimaryKey = dcaKey
' Declare a command builder to create SQL instructions
' to create and update records.
Dim cb = New OleDbCommandBuilder(daUsers)
' Update an existing record in the DataSet
Dim r As DataRow = dsUsers.Tables(0).Rows.Find(1)
If Not r Is Nothing Then
r("FirstName") = "Venus"
r("LastName") = "Williams"
' Update the record even in the database
daUsers.Update(dsUsers.GetChanges())
' Align in-memory data with the data source ones
dsUsers.AcceptChanges()
' Print successfully message
Console.WriteLine("The record has been updated successfully.")
Else
Console.WriteLine("No record found...")
End If
Catch ex As Exception
' Reject DataSet changes
dsUsers.RejectChanges()
' An error occurred. Show the error message
Console.WriteLine(ex.Message)
End Try
End Sub
End Class
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Employee.zip( 7 k)
