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Update Edmx When Database Changes in MVC 4

MVC 4: Update Edmx is to make the model as same as the database through which it created. Whatever changes made with the database will not reflect in the Model to perform CURD functions. Suppose we have added a new table with SQL server management studio and want to insert/update some entries with that table using code part. After creating object of database context, notice that we don’t have an instance for that newly added table. To resolve this issue we have to update our edmx using Update Model Wizard as described in this article.

Create new table Category in the same database added earlier and use basic columns like id, name, description, isActive. Open our visual studio project and check that this table have not any existence yet. Open edmx file, right click on the blank space and click on Update Model from Database.

Update Model from Database





  An Update Model wizard will open with options to add tables, views and stored procedures. We have added only a table so expand “Tables” node and select “Categories”. Leave remaining options as they are and click finish.


expand “Tables” node and select “Categories


 After finishing it will reload and will add newly added table, check the edmx file and there are two tables Employee and Categories as shown in below image.

check the edmx file


This update model wizard does following in MVC 4:
  • If a table removed from database, it will remove from the model also and update mapping details.
  • If table has been added, it will insert new object in the existing model and update mapping details.
  • Any modification in the object, this wizard will update the model like to add/remove columns.

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             In memory the linked list is stored in scattered cells (locations).The memory for each node is allocated dynamically means as and when required. So the Linked List can increase as per the user wish and the size is not fixed, it can vary.

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