Override for fluent NHibernate for long text strings nvarchar(MAX) not nvarchar(255)

Question

When ever you set a string value in fluent NHibernate it alwasy sets the DB vales to Nvarchar(255), I need to store quite a lot of long string which are based on user inputs

Answer 1

Hi I came across this Question, with the same problem. I have an slightly safer way of doing it as I don't want all string fields to have 10000 chars by default.

Firstly I register fluent nhibernate with some overrides

...//snip
....Mappings(m => m.AutoMappings.Add(
                    AutoMap.AssemblyOf()
                     //Use my mapping overrides here 
                    .UseOverridesFromAssemblyOf()
                    .Conventions.Add(new MyConventions()).IgnoreBase
                ))

My Mapping override class looks like this:

public class MyMappingOverride : IAutoMappingOverride {
       public void Override(AutoMapping mapping) {
           mapping.Map(x => x.LongName).Length(765);
       }
}

This is only required for small subset of entities with long text values. Maybe some else will find this useful?