Unable to update the EntitySet Table because it has a DefiningQuery and no InsertFunction element exists in the ModificationFunctionMapping element to support the current operation

ASP.NET MVC is the technology released from Microsoft long time back. But I didn’t get time to dig into it and research on it. Now, I need to learn it as my next project is in ASP.NET MVC. So, I thought to give a try and want to show all records in a table and insert a new record in a table. On the way, The above is the exception which blocked me to go proceed. I didn’t do any mistake and always the above exception come into picture when I try to create a new record in table.

So, frustrated and started research on the error and debugging. After a long research found the issue in the Entity framework. The whole thing is only because I forgot to add primary key to the table in the database. Once I added the primary key and reconstructed the edmx file with new changes, All works fine and record added to table in database. So, what is happening inside is, entity framework is looking for a key in each and every table [Primary key]. So, don’t forget to add a primary key to each and every table which you want to use in entity framework file [.edmx]. Otherwise you always see this exception when you try to insert or update a record.

"Unable to update the EntitySet 'Table' because it has a DefiningQuery and no <InsertFunction> element exists in the <ModificationFunctionMapping> element to support the current operation."

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