Nhibernate: Stop it from joining to a table that is not needed
- by Aaron
I have two tables (tbArea, tbPost) that relate to the following classes.
class Area
{
int ID
string Name
...
}
class Post
{
int ID
string Title
Area Area
...
}
These two classes map up with Fluent Nhibernate. Below is the post mapping.
public class PostMapping : ClassMap<Post>
{
public PostMapping()
{
Cache.NonStrictReadWrite();
this.Table("tbPost");
Id(x => x.ID)
.Column("PostID")
.GeneratedBy
.Identity();
References(x => x.Area)
.ForeignKey("AreaID")
.Column("AreaID");
...
}
}
Any time I perform a query on the Post table "where AreaID = 1(any AreaId)", nhibernate will join to the area table.
(What Nhibernate generates for a query)
SELECT
post fields
, area fields (automatically added)
FROM tbPost p
LEFT JOIN tbArea a on
p.areaid = a.areaid
where
p.areaid = 1
I have tried setting Area to LazyLoad, to Fetch.Select, ReadOnly, and any other setting on the reference and still it will always join to Area.
I am trying to optimize the backend database queries, and since I don't need the area object loaded just filtered I would like to eliminate the unnecessary join to Area each time I Query post.
What configurations do I need to change or mappings to get area to still be related to post in my objects, but not query it when I filter on AreaID?
