Question

Is it possible to convert this sort of query:

SELECT field1, field2 FROM table WHERE SHA1(field1 + field2) = 'hash'; 

into NHibernate’s Criteria language? E.g., something like:

session.CreateCriteria<Car>()
    .Add(Expression.Eq("SHA1(field1 + field2)", "hash"));

Answer 1

Perhaps this answer will work for you?

https://stackoverflow.com/a/797243

I would try something like:

ISQLFunction sqlAdd = new VarArgsSQLFunction("(", "+", ")");
var concat = Projections.SqlFunction(sqlAdd, NHibernateUtil.String, Projections.Property("ObjectProperty1"), Projections.Property("ObjectProperty2"));
var sha1 = Projections.SqlFunction("SHA1", NHibernateUtil.String, concat);
...
session.CreateCriteria<Car>().Add(Expression.Eq(sha1, "hash"));