Why is the SMO backup database progress bar not displayed in SQL Server?

The progress bar is not displayed when the SMO is used to back up the database, that is, the progress bar event PercentComplete is not triggered.

I tried it today. It's strange.

The Code is as follows:

Using Microsoft. SqlServer. Management. Smo;
Using Microsoft. SqlServer. Management. Common;
Private void btnBackup_Click (object sender, EventArgs e)
{
BtnBackup. Enabled = false;

Thread tr = new Thread (new ThreadStart (doBackup ));
Tr. Priority = ThreadPriority. AboveNormal;
Tr. Start ();
// Thread. Sleep (3000 );
}
/// <Summary>
/// Back up the database
/// </Summary>
Public void doBackup ()
{

PbDemo. Value = 0;
PbDemo. Maximum = 100;
PbDemo. Style = ProgressBarStyle. Blocks;
// PbDemo. Step = 10;

Server srv = new Server (@ "(local )");
Backup backup = new Backup ();

Backup. Action = BackupActionType. Database;
Backup. Database = "btnet ";
Backup. Incremental = false;

Backup. Devices. Add (new BackupDeviceItem (@ "C: \ agronet09.bak", DeviceType. File ));
Backup. Initialize = true;
Backup. PercentCompleteNotification = 10;
Backup. PercentComplete + = new PercentCompleteEventHandler (backup_PercentComplete );

// Backup. Checksum = true;

Backup. SqlBackup (srv );
}

Public void backup_PercentComplete (object sender, Microsoft. SqlServer. Management. Smo. PercentCompleteEventArgs e)
{
This. Invoke (new displayProgress_delegate (displayProgress), e. Percent );
// Application. DoEvents ();
}

Public delegate void displayProgress_delegate (int progress );

Public void displayProgress (int progress)
{
This. lbProgress. Text = "completed [" + progress. ToString () + "%]";
PbDemo. Value = progress;
BtnBackup. Enabled = (progress = 100 );

}

The results are correctly executed, but the progress bar is not displayed.

At first, I thought it was a thread problem. Later I found it was not the cause.

I tried another piece of code.

Using Microsoft. SqlServer. Management. Smo;
Using Microsoft. SqlServer. Management. Common;
Using System. Diagnostics;

Static void Main (string [] args)
{
BackupDatabase ("region \ agronet09", "agronet2008", "c: \ Northind_3.bak ");
Console. WriteLine (Environment. NewLine + "Press any key to continue .");
Console. ReadKey ();
}
Public static void BackupDatabase (string serverName, string databaseName, string fileName)
{
Console. WriteLine ("*** Backing up ***");
Server server = new Server (serverName );
Backup backup = new Backup ();
Backup. Action = BackupActionType. Database;
Backup. Database = databaseName;
Backup. Incremental = false;
Backup. Initialize = true;
Backup. LogTruncation = BackupTruncateLogType. Truncate;
BackupDeviceItem backupItemDevice = new BackupDeviceItem (fileName, DeviceType. File );
Backup. Devices. Add (backupItemDevice );
Backup. PercentCompleteNotification = 10;
Backup. PercentComplete + = backup_PercentComplete;
Backup. Complete + = backup_Complete;
Backup. SqlBackup (server );
}
Protected static void backup_PercentComplete (object sender, PercentCompleteEventArgs e)
{
Console. WriteLine (e. Percent + "% processed .");
// Application .();
System. Threading. Thread. Sleep (1000 );
}
Protected static void backup_Complete (object sender, ServerMessageEventArgs e)
{
Console. WriteLine (Environment. NewLine + e. ToString ());
}

The result is not displayed.

Later, I suddenly thought about whether the file was too small. I tried a m data file and it was displayed successfully:

After repeated experiments, we found that SQL server 2000 displays a progress bar when the data file is added with a log file larger than 6 MB.

The SQL server 2008 r2 displays a progress bar at about 3 m. It may be related to machines.

Note: SQL server 2008 r2 requires that the primary data file must be greater than 3 MB!

References:

Http://msdn.microsoft.com/zh-cn/magazine/cc163409.aspx

DEMO code download