I have created database project using VS 2012. Once the schema comparison is done, the update target button should be enabled to sync with target.
But it\'s not get
Workaround 2:
In my case, the Update button was greyed out because of there were errors warnings about a view that I created and added to the project earlier. The problem was that the view was scripted to use full database qualified object naming. E.g. [databasename].[schemaname].[objectname], which works fine in SSMS, but causes a problem when it is checked in a DB Project. If you use three part naming for referring an object in same DB project results in a error/warning in Visual Studio.
By changing the code to [schemaname].[objectname] in the definicion of the view removed the error warnings and enable the Update option. Happy days!
Credits: https://visualstudio.uservoice.com/forums/121579-visual-studio-ide/suggestions/3577074-allow-three-part-naming-for-referring-a-db-object
https://visualstudio.uservoice.com/forums/121579-visual-studio-ide/suggestions/17396128-keep-update-and-generate-update-script-buttons