how to change model without losing data in entity framework

Question

please tell me  how to change model in entity framework  without losing data in existing database . when we change model first database deleted and then create new database and i lost existing data.

 

Answer 1

Hi,

I hope you are talking about code first approach

once you create database using code first approach then after that if you want to change the model class . that reflect your database

if you do not want loose any column value then use migration

here is step

open your package manager console type the following comand

1. enable-migrations

2. add-migration

3. update-database

when ever you change the model class repeat the second and third step

 

for more details  check this

 

http://www.c-sharpcorner.com/UploadFile/4b0136/perform-code-first-migration-in-Asp-Net-mvc-5/ 

Answer 2

I think you are saying about Migration.

Visit here:-

http://www.dotnet-tricks.com/Tutorial/entityframework/R54K181213-Understanding-Entity-Framework-Code-First-Migrations.html