SqlTransaction.Rollback Method

Definition

Namespace:

System.Data.SqlClient

Assembly:

System.Data.SqlClient.dll

Package:

System.Data.SqlClient v4.9.0

Rolls back a transaction from a pending state.

Overloads

Rollback()	Rolls back a transaction from a pending state.
Rollback(String)	Rolls back a transaction from a pending state, and specifies the transaction or savepoint name.

Rollback()

Source:

System.Data.SqlClient.notsupported.cs

Rolls back a transaction from a pending state.

C#

public override void Rollback();

Exceptions

Exception

An error occurred while trying to commit the transaction.

InvalidOperationException

The transaction has already been committed or rolled back.

-or-

The connection is broken.

Examples

The following example creates a SqlConnection and a SqlTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods. The transaction is rolled back on any error. Try/Catch error handling is used to handle any errors when attempting to commit or roll back the transaction.

C#

private static void ExecuteSqlTransaction(string connectionString)
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        SqlCommand command = connection.CreateCommand();
        SqlTransaction transaction;

        // Start a local transaction.
        transaction = connection.BeginTransaction();

        // Must assign both transaction object and connection
        // to Command object for a pending local transaction
        command.Connection = connection;
        command.Transaction = transaction;

        try
        {
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Attempt to commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType());
            Console.WriteLine("  Message: {0}", ex.Message);

            // Attempt to roll back the transaction.
            try
            {
                transaction.Rollback();
            }
            catch (Exception ex2)
            {
                // This catch block will handle any errors that may have occurred
                // on the server that would cause the rollback to fail, such as
                // a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType());
                Console.WriteLine("  Message: {0}", ex2.Message);
            }
        }
    }
}

Remarks

The Rollback method is equivalent to the Transact-SQL ROLLBACK TRANSACTION statement. For more information, see ROLLBACK TRANSACTION (Transact-SQL) .

The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called). The transaction is rolled back in the event it is disposed before Commit or Rollback is called.

Megjegyzés

Try/Catch exception handling should always be used when rolling back a transaction. A Rollback generates an InvalidOperationException if the connection is terminated or if the transaction has already been rolled back on the server.

For more information on SQL Server transactions, see Transactions (Transact-SQL).

See also

• Local Transactions
• ADO.NET Overview

Rollback(String)

Source:

System.Data.SqlClient.notsupported.cs

Rolls back a transaction from a pending state, and specifies the transaction or savepoint name.

C#

public void Rollback(string transactionName);

Parameters

transactionName

String

The name of the transaction to roll back, or the savepoint to which to roll back.

Exceptions

ArgumentException

No transaction name was specified.

InvalidOperationException

The transaction has already been committed or rolled back.

-or-

The connection is broken.

Examples

The following example creates a SqlConnection and a SqlTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods. The transaction is rolled back on any error. Try/Catch error handling is used to handle any errors when attempting to commit or roll back the transaction.

C#

private static void ExecuteSqlTransaction(string connectionString)
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        SqlCommand command = connection.CreateCommand();
        SqlTransaction transaction;

        // Start a local transaction.
        transaction = connection.BeginTransaction("SampleTransaction");

        // Must assign both transaction object and connection
        // to Command object for a pending local transaction
        command.Connection = connection;
        command.Transaction = transaction;

        try
        {
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Attempt to commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Commit Exception Type: {0}", ex.GetType());
            Console.WriteLine("  Message: {0}", ex.Message);

            // Attempt to roll back the transaction.
            try
            {
                transaction.Rollback("SampleTransaction");
            }
            catch (Exception ex2)
            {
                // This catch block will handle any errors that may have occurred
                // on the server that would cause the rollback to fail, such as
                // a closed connection.
                Console.WriteLine("Rollback Exception Type: {0}", ex2.GetType());
                Console.WriteLine("  Message: {0}", ex2.Message);
            }
        }
    }
}

Remarks

The Rollback method is equivalent to the Transact-SQL ROLLBACK TRANSACTION statement. For more information, see Transactions (Transact-SQL).

The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called). The transaction is rolled back if it is disposed before Commit or Rollback is called.

Megjegyzés

Try/Catch exception handling should always be used when rolling back a transaction. A Rollback generates an InvalidOperationException if the connection is terminated or if the transaction has already been rolled back on the server.

For more information on SQL Server transactions, see Transactions (Transact-SQL).

See also

• Performing a Transaction
• ADO.NET Overview