Ignoring accents in SQL Server using LINQ to SQL

Question

How can I ignore accents (like ´, `, ~) in queries made to a SQL Server database using LINQ to SQL?

UPDATE:

Still haven\'t figured out how t

Answer 1

In SQL queries (Sql Server 2000+, as I recall), you do this by doing something like select MyString, MyId from MyTable where MyString collate Latin1_General_CI_AI ='aaaa'.

I'm not sure if this is possible in Linq, but someone more cozy with Linq can probably translate.

If you are ok with sorting and select/where queries ALWAYS ignoring accents, you can alter the table to specify the same collation on the field(s) with which you are concerned.

Answer 2

It seems that there is a way to ignore the collation differences in Linq to SQL by using t-sql functions:

CREATE FUNCTION [dbo].[func_ConcatWithoutCollation]
(
    @param1 varchar(2000),
    @param2 varchar(2000)
)
RETURNS varchar(4000)
AS
BEGIN
    IF (@param1 IS NULL) SET @param1 = ''
    IF (@param2 IS NULL) SET @param2 = ''
    RETURN @param1 COLLATE Latin1_General_CS_AS + @param2 COLLATE Latin1_General_CS_AS
END

to get this function in linq to sql, there is a switch for SqlMetal: /functions. Example:

"%ProgramFiles%\Microsoft SDKs\Windows\v7.0A\Bin\SqlMetal.exe" /server:. /database:NameOfDatabase /pluralize /code:ContextGenerated.cs /sprocs /views /functions

Use this function in Linq to sql like this:

from s in context.Services
where context.Func_ConcatWithoutCollation(s.Description, s.Email) == "whatever"
select s

It helped me, maybe somebody finds this useful too.

Answer 3

See the following answer:

LINQ Where Ignore Accentuation and Case

Basically you need to alter the field type in SQL Server, e.g.

ALTER TABLE People ALTER COLUMN Name [varchar](100) COLLATE SQL_Latin1_General_CP1_CI_AI

There does not seem to be a way to do this using LINQ, apart from calling a custom method to remove diacritics (which would not be performant).

Answer 4

LINQ to SQL doesn't have any specific functionality for setting the collation used for a query and so it will always use the database default.