MySqlConnection.BeginTransaction Method (IsolationLevel)

MySQL Connector/Net

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MySqlConnectionBeginTransaction Method (IsolationLevel)
Begins a database transaction with the specified isolation level.

Namespace: MySql.Data.MySqlClient
Assembly: MySql.Data (in MySql.Data.dll) Version: 6.9.9
Syntax
Copy
public MySqlTransaction BeginTransaction(
	IsolationLevel iso
)
Public Function BeginTransaction ( 
	iso As IsolationLevel
) As MySqlTransaction
public:
MySqlTransaction^ BeginTransaction(
	IsolationLevel iso
)
member BeginTransaction : 
        iso : IsolationLevel -> MySqlTransaction

Parameters

iso
Type: System.DataIsolationLevel
The isolation level under which the transaction should run.

Return Value

Type: MySqlTransaction
An object representing the new transaction.
Exceptions
ExceptionCondition
InvalidOperationExceptionParallel exceptions are not supported.
Remarks

This command is equivalent to the MySQL BEGIN TRANSACTION command.

You must explicitly commit or roll back the transaction using the Commit or Rollback method.

Note Note
If you do not specify an isolation level, the default isolation level is used. To specify an isolation level with the BeginTransaction method, use the overload that takes the iso parameter. Also note that any attempt to begin a transaction while a transaction is in progress will throw an exception on MySQL 4.1 and higher. On MySQL 4.0, an exception will not be thrown because servers 4.0 and earlier did not report their transacation status.

Examples
The following example creates a MySqlConnection and a MySqlTransaction. It also demonstrates how to use the BeginTransaction, a Commit, and Rollback methods.
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public void RunTransaction(string myConnString)
{
MySqlConnection myConnection = new MySqlConnection(myConnString);
myConnection.Open();

MySqlCommand myCommand = myConnection.CreateCommand();
MySqlTransaction myTrans;

// Start a local transaction
myTrans = myConnection.BeginTransaction();
// Must assign both transaction object and connection
// to Command object for a pending local transaction
myCommand.Connection = myConnection;
myCommand.Transaction = myTrans;

try
{
myCommand.CommandText = "insert into Test (id, desc) VALUES (100, 'Description')";
myCommand.ExecuteNonQuery();
myCommand.CommandText = "insert into Test (id, desc) VALUES (101, 'Description')";
myCommand.ExecuteNonQuery();
myTrans.Commit();
Console.WriteLine("Both records are written to database.");
}
catch(Exception e)
{
try
{
myTrans.Rollback();
}
catch (SqlException ex)
{
if (myTrans.Connection != null)
{
Console.WriteLine("An exception of type " + ex.GetType() +
" was encountered while attempting to roll back the transaction.");
}
}

Console.WriteLine("An exception of type " + e.GetType() +
" was encountered while inserting the data.");
Console.WriteLine("Neither record was written to database.");
}
finally
{
myConnection.Close();
}
}
Public Sub RunTransaction(myConnString As String)
Dim myConnection As New MySqlConnection(myConnString)
myConnection.Open()

Dim myCommand As MySqlCommand = myConnection.CreateCommand()
Dim myTrans As MySqlTransaction

' Start a local transaction
myTrans = myConnection.BeginTransaction()
' Must assign both transaction object and connection
' to Command object for a pending local transaction
myCommand.Connection = myConnection
myCommand.Transaction = myTrans

Try
myCommand.CommandText = "Insert into Test (id, desc) VALUES (100, 'Description')"
myCommand.ExecuteNonQuery()
myCommand.CommandText = "Insert into Test (id, desc) VALUES (101, 'Description')"
myCommand.ExecuteNonQuery()
myTrans.Commit()
Console.WriteLine("Both records are written to database.")
Catch e As Exception
Try
myTrans.Rollback()
Catch ex As MySqlException
If Not myTrans.Connection Is Nothing Then
Console.WriteLine("An exception of type " + ex.GetType().ToString() + _
" was encountered while attempting to roll back the transaction.")
End If
End Try

Console.WriteLine("An exception of type " + e.GetType().ToString() + _
"was encountered while inserting the data.")
Console.WriteLine("Neither record was written to database.")
Finally
myConnection.Close()
End Try
End Sub

No code example is currently available or this language may not be supported.

No code example is currently available or this language may not be supported.

See Also
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