Entity Framework Working with Transactions

namespace TransactionsExamples 
{ 
    class TransactionsExample 
    { 
        static void StartOwnTransactionWithinContext() 
        { 
            using (var context = new BloggingContext()) 
            { 
                using (var dbContextTransaction = context.Database.BeginTransaction()) 
                { 
                    try 
                    { 
                        context.Database.ExecuteSqlCommand( 
                            @"UPDATE Blogs SET Rating = 5" + 
                                " WHERE Name LIKE '%Entity Framework%'" 
                            ); 
 
                        var query = context.Posts.Where(p => p.Blog.Rating >= 5); 
                        foreach (var post in query) 
                        { 
                            post.Title += "[Cool Blog]"; 
                        } 
 
                        context.SaveChanges(); 
 
                        dbContextTransaction.Commit(); 
                    } 
                    catch (Exception) 
                    { 
                        dbContextTransaction.Rollback(); 
                    } 
                } 
            } 
        } 
    } 
}

namespace TransactionsExamples 
{ 
     class TransactionsExample 
     { 
        static void UsingExternalTransaction() 
        { 
            using (var conn = new SqlConnection("...")) 
            { 
               conn.Open(); 
 
               using (var sqlTxn = conn.BeginTransaction(System.Data.IsolationLevel.Snapshot)) 
               { 
                   try 
                   { 
                       var sqlCommand = new SqlCommand(); 
                       sqlCommand.Connection = conn; 
                       sqlCommand.Transaction = sqlTxn; 
                       sqlCommand.CommandText = 
                           @"UPDATE Blogs SET Rating = 5" + 
                            " WHERE Name LIKE '%Entity Framework%'"; 
                       sqlCommand.ExecuteNonQuery(); 
 
                       using (var context =  
                         new BloggingContext(conn, contextOwnsConnection: false)) 
                        { 
                            context.Database.UseTransaction(sqlTxn); 
 
                            var query =  context.Posts.Where(p => p.Blog.Rating >= 5); 
                            foreach (var post in query) 
                            { 
                                post.Title += "[Cool Blog]"; 
                            } 
                           context.SaveChanges(); 
                        } 
 
                        sqlTxn.Commit(); 
                    } 
                    catch (Exception) 
                    { 
                        sqlTxn.Rollback(); 
                    } 
                } 
            } 
        } 
    } 
}

namespace TransactionsExamples 
{ 
    class TransactionsExample 
    { 
        static void UsingTransactionScope() 
        { 
            using (var scope = new TransactionScope(TransactionScopeOption.Required)) 
            { 
                using (var conn = new SqlConnection("...")) 
                { 
                    conn.Open(); 
 
                    var sqlCommand = new SqlCommand(); 
                    sqlCommand.Connection = conn; 
                    sqlCommand.CommandText = 
                        @"UPDATE Blogs SET Rating = 5" + 
                            " WHERE Name LIKE '%Entity Framework%'"; 
                    sqlCommand.ExecuteNonQuery(); 
 
                    using (var context = 
                        new BloggingContext(conn, contextOwnsConnection: false)) 
                    { 
                        var query = context.Posts.Where(p => p.Blog.Rating > 5); 
                        foreach (var post in query) 
                        { 
                            post.Title += "[Cool Blog]"; 
                        } 
                        context.SaveChanges(); 
                    } 
                } 
 
                scope.Complete(); 
            } 
        } 
    } 
}