how to add new table to existing entity model without losing any customisation to model?

I 开发者_开发技巧want to add a new table in my existing entity data model without using the option update from database. Because in this case i loss existing modification like inheritance and entity names.

Right click, add new entity, and then manually fill out the Property and Navigation properties. Then look for a tab ( usually at the bottom ) called mapping details, thats where you specify how the columns map up.