Using MySQL community server in one of the projects I have been working on. Few days back I reset my machine and installed latest version of MySQL server - v5.7.12 (development mode).
This started giving me error on "update from source" in EntityFramework (EDMX) - design first approach.
Unexpected exception occurred when generating the model. See output window for more details. Exception message : 'StrongTypingException: The value for column 'IsPrimaryKey' in table 'TableDetails' is DBNull.'.
I was able to solve the issue in most simplest way possible is to downgrade to MySQL Server Version 5.6.30
There might be other ways to fix it with latest version of MySQL server but this was the straight forward fix I can use to get around this issue and IT WORKED.
Hope it helps other developer stuck in same situation.