NHibernate将字符串参数转换为nvarchar而不是varchar。我该如何阻止呢?

I have a class mapped to a view and am searching on first and last names in order to search for patient records. The view ultimately looks at the first and last name fields on the patient table (possibly others as well depending on input). When the criteria converts to SQL, it's entering my strings as nvarchar parameters. I've already used type="AnsiString" and length="50" on my mapping, but it still is converting these to nvarchar, which is causing a performance hit on my query.I have a class mapped to a view and am searchin