To attain a smooth and trouble-free upgrade to SQL Server 2014, you must plan for the upgrade and address the complexities of your application.This document takes you through the essential technical details for planning and testing an upgrade of existing SQL Server 2005, 2008, 2008 R2, and 2012 instances to SQL Server 2014. You will be presented with best practices for preparation, planning, pre-upgrade tasks, and post-upgrade tasks. All the SQL Server components are covered, each in its own chapter.
This document is a supplement to SQL Server 2014 Books Online. It is not intended to supersede any information in SQL Server Books Online or in the Microsoft Knowledge Base articles.
Link to the 429 page comprehensive technical guide: here. Remember to start planning your upgrades now as the end of extended support for SQL Server 2005 is on April 12, 2016. For more information see - http://www.microsoft.com/en-us/server-cloud/products/sql-server-2005/ and remember if you have any applications that don't support SQL Server 2014, you can nominate them by sending an email to mailto:email@example.com with details of the application name, vendor name, version number, etc. Our ISV teams can assist the application vendor with the upgrade process.