I've been using SQL Server for quite sometime and I have management problems about my large scale projects.
I was wondering how others manage their large scale projects.
No so much clear about " I have management problems about my large scale projects", are you talking about how to organize the structure of the source code? Which tool do you use for this, from my experience, I can suggest you the use of Visual Studio + SSDT, this allows you to have once solution organized per Database, internally it will organize a snapshot, it means, a project which will be organized on common objects like tables, functions, stored procedures, etc. Another great benefit is the use of Dacpac technology that you can use for creating a new Database from scratch with the same structure on it was based on.
In Visual Studio 2017 you have some amazing RedGate tool included (free), but I believe that you can take advantage of VS per se, I have not had any problem in terms of productivity with the use of Visual Studio.