private void UndoLog()
{
if (!Database.Get().TransactionManager.IsTransactionActive)
{
return;
}
List <LogRecordTable> logRecordsToBeUndone = GetLogToBeUndone();
List <LogRecordUndo> logRecordsUndone = GetUndoneLog();
// Do not undo log records we have undone on the previous recovery.
//
foreach (LogRecordUndo logRecordUndo in logRecordsUndone)
{
LogRecordTable logRecordToBeUndone = logRecordsToBeUndone.First();
if (!logRecordUndo.LogRecordTable.Equals(logRecordToBeUndone))
{
throw new Exception("We did not undo properly the last time around.");
}
logRecordsToBeUndone.RemoveAt(0);
}
// Undo log.
//
foreach (LogRecordTable logRecord in logRecordsToBeUndone)
{
LogRecordUndo logRecordUndo = new LogRecordUndo(logRecord);
PersistLogRecord(logRecordUndo);
logRecordUndo.Redo();
}
// Complete the transaction so we can open a new one later.
// Also, this would be signal on the recovery not to undo this part of the log again.
//
Database.Get().TransactionManager.EndTransaction();
}
public abstract void UndoRowOperation(LogRecordUndo logRecordUndo, Table table);
public override void Undo(LogRecordUndo logRecordUndo)
{
UndoRowOperation(logRecordUndo, GetTable());
}