Entity Framework - case insensitive Contains?

Question

I want a solution to this problem that does not involve ToUpper or ToLower, as I use in the code below;

var upper = term.ToUpper(); using (var db = this.DataContext) {     return db.Counties.Where(x => x.CountyName.ToUpper().Contains(upper)).ToList(); } 

I am using entitly framework so the C# solution of using StringComparison.CurrentCultureIgnoreCase does not work. It does work for Equals, EndsWith and StartsWith, but not Contains.

Answer 1

I use EF6 and Sql Server and Contains is mapped to LIKE '%@p0%' which is case insensitive in my case. So in my case:

db.Counties.Where(x => x.CountyName.Contains(term)).ToList(); 

works as needed. More info in Sjoerd answer.

Answer 2

I know that this is not related directly to EF, but only solution I can think of is to alter DB table column collation to be Case Insensitive e.g.:

ALTER TABLE TABLENAME ALTER COLUMN COLUMNNAME nvarchar(100) COLLATE Latin1_General_CI_AS NULL 

CI - case insensitive / CS - case sensitive

AS - accent sensitive / AI - accent insensitive (can also be useful)

If you can't change collation of table column you can use direct query from EF with forcing collation

select *  from table where country collate Latin1_General_CI_AS != @country