Best way to map a hidden property in NHibernate (fluent)
I know this question could lead to a subjective answer, but I'd like to get an opinion from someone else.
Some 开发者_JAVA技巧background Currently I have a class that maps a private string property to a geometry column in a PostgreSQL (PostGIS) database table along with a public string for WKT. The WKT is used by PostGIS to automatically update the geometry column, using a trigger. As I don't want to include any spatial references in my domain model, all querying is done using WKT strings and a custom spatial criterion, which wraps the WKT in a spatial PostGIS function and queries the private geometry property column reference. All of this works as expected.
The question Since I need the column reference, I also need the property in my domainmodel, for NHibernate to map to, so I was wondering, what the best solution would be, for NHibernate to never select this property.
My current solution looks as follows with Fluent NHibernate:
Map(Reveal.Member<LocationReference>("Geometry"), "geometry")
.Generated.Always()
.ReadOnly()
.LazyLoad();
This does the trick, and when I select the entity, I won't get the property, unless I manually load it (which isn't possible through the lambda extensions). Unfortunately I would still be able to do a Criteria or HQL query for the property.
So are there any ways for me to do anything that prevents NHibernate from being able to do ever include the column in a select? Or is the above solution the only way to at least ignore the column when selecting with Query<>
or QueryOver<>
?
Well, I ended up removing the mapped property, because, even though it was lazy, NHibernate would sometimes load it anyway. What I did was actually a bit of a hack. I needed the alias for a property from the same class, so I used the mapping from another property and split the SqlString
on '.
', to get the correct alias.
All of this makes perfect sense to me, and the "workaround" is not nice, but I don't see any other way of doing it. NHibernate needs to know, what property it's dealing with, to assign proper aliases. Since I'm not mapping the property, it has no way of knowing, what alias I'm looking for.
I guess I'm doing a lot of hacking, just to avoid having to reference NHibernate.Spatial...
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