Difference between Backup/Restore and Export/Import

Backup-SPSite:

Backup-SPSite is generally used when you want to replicate the entire site collection (including all subsites) to an existing web application.

It allows you to backup either a site collection or web application.
You can basically consider the file generated more or less as a SQL dump of (a part of) your content database.It preserves the GUID of every object except the GUID of the Site.
When you restore the backup, SharePoint generates a new GUID for the site collection.

Export-SPWeb:
Export-SPWeb is generally used when you want to replicate just a single subsite to an existing site collection, that allows you to backup data of a sub site (SPWeb object), but it can also export a site collection, an entire web application, or a single list. It generates a new GUID for every objects such as sites, sub sites, lists and items.

A major drawback of this operation is that it does not preserves workflows instances, associations, history and tasks.Every workflow association must be recreated and there is no way to restore the running instances from original site.

Export/import is often used to split site collections into multiple pieces when they reached a certain limit. Or to do the vice versa and consolidate multiple site collections into one larger one. Both of these actions work fine as long as the migrated content does not use the publishing feature.

Example for Subsite backup and restore:

Export-SPWeb -Identity http://spsdemo:9999/Subsite1 -Path "D:\Exports\Subsite1"
Import-SPWeb http://spsdemo:6666/Subsite2 -Path "D:\Exports\Subsite1.cmp"

Example for list backup and restore:

Export-SPWeb http://spsdemo:9999/ -ItemUrl "/Lists/Test%20docs/" -Path "D:\Exports\TestDoc"
Import-SPWeb -Identity http://spsdemo:6666 -Path "D:\Exports\TestDoc.cmp"

Programmatically how to create backup and restore a sitecolletion in SharePoint 2010

In previous post, have seen how to take backup and restore a site collection using power shell commands.

Here will take back up and restore a site collection using SharePoint API.

There are two methods to create back up and restore a site collection.

1. Backup and

2. Restore.

Here i want to maintain one log file for tracing backup and restore creation details, so for that created the following method.

here we need to create two folder in D drive for saving backup file and log file.

D:\SiteBackupLog and D:\SiteBackUp

        public static void siteBackupLog(string message)

        {

            string PathName = "D:\\SiteBackupLog\\";

     PathName = PathName + "Backuplog-" + DateTime.Now.ToString("dd-MM-yyyy") + ".log";

            StreamWriter sw = new StreamWriter(PathName, true);

            sw.WriteLine(message + " - " + DateTime.Now);

            sw.Flush();

            sw.Close();

        }

Now , for taking backup of a site collection , used the following method.

        private void btnBackup_Click(object sender, EventArgs e)

        {

            string sourceSiteCollURL = "http://ukreddy:6969";

            string time = DateTime.Now.ToString("dd-MM-yyyy");

            string backupfilename = "D:\\SiteBackup\\SharePointSiteBackup_" + time + ".bak";

            siteBackup(sourceSiteCollURL, backupfilename);

        }

        public static void siteBackup(string siteURL, string fileName)

        {

            try

            {

                SPSecurity.RunWithElevatedPrivileges(delegate()

                {

                    SPWebApplication webApplication = null;

                    webApplication = SPWebApplication.Lookup(new Uri(siteURL));

                    SPSiteCollection sitecols = webApplication.Sites;

                    string backupName = fileName;

                    sitecols.Backup(siteURL, backupName, true);//true is used for if already bak file created with the same name , it will overwrite

                });

                siteBackupLog("Site Collection backup created succuessfully");

            }

            catch (Exception ex)

            {

                siteBackupLog(ex.Message);

            }

        }  

in the above code we are try to create backup file and saving it in the specified location and also writing log also.

And the following code is used to restore site collection in new web application i.e http://ukreddy:2727 and restore it as root site collection.

        private void btnRestore_Click(object sender, EventArgs e)

        {

            string sitecollectionURL = "http://ukreddy:2727";

            string backupfilename = "D:\\SiteBackup\\SharePointSiteBackup_27-10-2012.bak";

            SiteRestore(sitecollectionURL, backupfilename);

        }

        private void SiteRestore(string siteURL, string fileName)

        {

            try

            {

                SPSecurity.RunWithElevatedPrivileges(delegate()

                {

                    SPWebApplication webApplication = null;

                    webApplication = SPWebApplication.Lookup(new Uri(siteURL));

                    SPSiteCollection sitecols = webApplication.Sites;

                sitecols.Restore("/", fileName, true);// overwrite sitecollection if already exists

                });

                siteBackupLog("Site collection restored successfully");

            }

            catch (Exception ex)

            {

               siteBackupLog(ex.Message);

            }

        }

here the screen shot of actual site collection i.e http://ukreddy:6969 and restored site collection i.e http://ukreddy:2727 respectively.

Thats it...

pls let me know if u have questions/suggestions.