lambda query data like sql where not in - sql-server

Question

in my database i save users tag in table
the table structure is
Table Name : User
Id Name Tags
1 Jack White,Yellow,Green
2 smith Yellow,Green
3 smith Blank
....
the condition is:
string[] tags = {"Yellow","Green"};
I hope can get the data from database,so this is my lambda:
unitOfWork.Repository<User>().find(x=>!x.Any(x.Tag.......);
the sql like:
Select * from Users Where Tags not in('Yellow','Green')
but the tags in database is long string with ","

Answer 1

If you have big data, this is not a good solution But you can after you select all data.
var result = db.Users.ToList()
.Where(i => i.Tags.Split(',').Any(t => tags.Contains(t))).ToList();
I think, normalize your schema looks like better.
Other option:
You can use SqlQuery
class Users
{
public int Id { get; set; }
public string Name { get; set; }
public string Tags { get; set; }
}
string[] tags = {"Yellow","Green"};
var whereClause = String.Join(" OR ", tags.Select(i => String.Format("Tags LIKE %{0}%", i));
var query = String.Format(#"
SELECT
*
FROM
Users
Where
{0}
", whereClause);
var result = dbContext.Database.SqlQuery<Users>(query);
Query looks like:
SELECT
*
FROM
Users
Where
Tags LIKE %Yellow% OR Tags LIKE %Green%