How to generate an mdf file if the first call to the database is a select query?

Question

C++ / C#

There is a model, there is a context. The file seems to be generated when data is added to the table, but first I search for matches between the inserted data and what is in the table. How to be?

Answer 1

My connection string was incorrect. In VS2015, you need to write not (localdb)\v11.0, but (localdb)\MSSQLLocalDB( source ).

Answer 2

One in the title, another in the description.
Here is metanit.com/sharp/entityframework

Answer 3

Database initialization metanit.com/sharp/entityframework/3.9.php please.
It's easier to make a unique index, and catch exceptions when inserting data that exists.