How to develop a database (workflow)?
I can only tell you what we do now and what I have done in the past. Our shop uses MSTFS (Microsoft Team Foundation Server), so any version we have the ability to get the latest version of the script.

When we create the scripts we include the customary header - Description, Date, Author, Title, and sometimes Build number. This helps us to maintain code versioning and build numbers with database code.

We branch SQL code with functional code so as we integrate branches from developers, their SQL code comes with. When we moved to production, it all moved together.

In other positions, the data group worked with developers to create the database ERD. Then the data group came in as another branch to the project and create database objects. When the functional code was complete and the move was going to production, their branch was deployed to the data tier while the code was deployed to the app tier. The members of the DEVOPS group tied it all together. 

There are many ways you can go. You just have to pick one. I suggest reading further on Application Lifecycle Management (ALM).

Typical ALM treats DB versioning like an afterthought if at all. Many companies treat the DB in the same fashion. 

The answer is, it depends. I use a tool (MySQL Workbench, VS) to script my database object creation and I version the scripts based on build number. Typically it's YYYYMMDD#. Most DB tools are rudimentary so your mileage may vary. Try some different methods and find what works for you.