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Isolation Level ReadUncommitted

Imports System Imports System.Xml Imports System.Xml.Schema Imports System.IO Imports System.Data.SqlClient Imports System.Collections Imports System.Data Public Class MainClass          Shared Sub Main()         Dim myconnection1, myconnection2 As SqlConnection         Dim mycommand1, mycommand2 As SqlCommand         Dim mytransaction1, mytransaction2 As SqlTransaction         Dim myreader As SqlDataReader         Dim ConnectionString As String         'open a database connection         ConnectionString = "Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI"         myconnection1 = New SqlConnection(ConnectionString)         myconnection2 = New SqlConnection(ConnectionString)         Try             myconnection1.Open()             myconnection2.Open()             'start a transaction             mytransaction1 = myconnection1.BeginTransaction()             mytransaction2 = myconnection2.BeginTransaction(IsolationLevel.ReadUncommitted)             mycommand1 = New SqlCommand()             mycommand1.Connection = myconnection1             mycommand1.Transaction = mytransaction1             mycommand2 = New SqlCommand()             mycommand2.Connection = myconnection2             mycommand2.Transaction = mytransaction2             mycommand1.CommandText = "insert into Employee  values (101, 'F', 'L')"             mycommand1.ExecuteNonQuery()             mycommand1.CommandText = "insert into Employee values (101, 'F', 'L')"             mycommand1.ExecuteNonQuery()             mycommand2.CommandText = "select * from Employee"             myreader = mycommand2.ExecuteReader()             Console.WriteLine("Last 2 Orders - Transaction is pending")             Console.WriteLine("======================================")             While myreader.Read()                 Console.WriteLine(myreader.GetInt32(0))             End While             myreader.Close()             Console.ReadLine()             mytransaction1.Rollback()             mycommand2.CommandText = "select * from Employee"             myreader = mycommand2.ExecuteReader()             Console.WriteLine("Last 2 Orders - Transaction rolled back")             Console.WriteLine("=======================================")             While myreader.Read()                 Console.WriteLine(myreader.GetInt32(0))             End While             Console.ReadLine()         Catch e As Exception             Console.WriteLine(e.Message)         Finally             myconnection1.Close()             myconnection2.Close()         End Try     End Sub End Class