Can we restore a database which is created and have some data in SQL Server 2012. But, now i want to migrate from SQL Server 2012 to SQL Server 2017. Is it possible to take backup in SQL Server 2012 and restore it to SQL Server 2017. I need some other solutions if not possible to restore it. Because, it's almost 30GB of data, i can't get it back if not possible to restore.
Yes, SQL Server is backward compatible. You can restore a database from any previous version of SQL Server that was supported at the time of the release. For SQL Server 2017, you can therefore restore databases from SQL Server 2008 to 2017.
SQL Server, however, is not forward compatible. Once a database is restored on a more recent version of SQL Server you cannot create a back up of that database and restore it to an older version; even if the database had the correct compatibility setting. The upgrade process is one way.