How to Update Column based on another table column value

Question

I have two data tables

table

id  isfav
---------
1   1
2   1
3   1
4   1
5   1

favtable id 
-----------    
  2    true
  3    false

So I want to update the table1 column isFav to 0 if the ids exist in FavTable with false.

Can anybody help me with this?

Answer 1

You can use Any() to search in other entities.

var db = new YourDbContext();
var favtable = db.favtable.ToList();

//Find them:
var result = db.Table1.Where(t => favtable.Any(f => f.id == t.id && !f.isfav));

//result should be 3.

.NET Fiddle: https://dotnetfiddle.net/BmaqN5