***Backgroud:***
EDMX was built pretty straight forward, I just selected all tables and clicked "Ok" button several times, the thing is, not all the columns are/will be consumed by system.

***What happened***
Later on, several nice-to-have columns became "kiss-good-bye" columns, and bam, several components stopped functioning as exceptions are thrown from entity framework saying "Invalid Column Name xxxxx"

***What is wanted to be achieved***
Hopefully the legendary gurus in stackoverflow will kindly shine light on "how to let EF ignore unused columns, even if they are no more in DB".

System design sometimes would like some room. so there go all the candidate columns that might not be in use after a while, yet DB-First approach takes in all the candidates, it's possible for MS to come up with some kind of a policy to ignore unused properties, and the complexity and cost to implement this mechanism seems not very high.

In Following there lays a few things I tried but didn't have any luck, maybe it's the way I tried it, or it's just not the thing to turn things around.

***Method #1 tried on my side***

Implementing data loading in a more column-specific way, Table1.Select(Column1, 2, 3, 4);
Why I dropped it: it's just too much for me to rewrite so I didn't even verify whether it solves the problem.

***Method #2 tried on my side***

Why I dropped it: it just doesn't work

***Method #3***

DefaultValue=""

Why I dropped it: it just doesn't work, still got "invalid column name" exception

***#4***

Database.SetInitialize

Why I dropped it: it doesn't work