update and delete instead of just delete?

Mare · **Joined:** Mon Nov 19, 2007 6:43 am **Posts:** 6

Hy,

I have classical one-to-many relationship (parent - childs). In DB child entity has foreign key on parent.
I read parent with lazy="true", so I get all childs automatically. I remove one child from parent.Child collection (I use Set) and when I try to save parent object I see in SQL profiler that NH generated two statements 1st: update child row.FK_field = null and 2nd delete statement?

How can I get just delete statement. Because now (as described above) I must allow nulls on child.FK_field in DB and for my model that is not OK.

tenx

wilbur4321 · **Joined:** Mon Dec 03, 2007 10:50 pm **Posts:** 6

Do you have a not-null="true" attribute on the parent property of the child object?

--randy

Mare · **Joined:** Mon Nov 19, 2007 6:43 am **Posts:** 6

Yes,

tag for that fk field on child entity is like this:

<many-to-one name="parent" column="PARENT_ID" not-null="true" outer-join="auto"></many-to-one>

tenx ...

Nels_P_Olsen · **Posted:** Tue Dec 04, 2007 6:45 pm

We have the same issue. Since our entities implement a specific interface that tracks dirty and deleted status, we were able to do this in IInterceptor.FindDirty:

Code:

public int[] FindDirty(
   object   entity,
   object   id,
   object[] currentState,
   object[] previousState,
   string[] propertyNames,
   NHibernate.Type.IType[] types)
{
   OurCompany.BLL.IEntity ent = entity as OurCompany.BLL.IEntity;

   if (!this.IsChanged(ent) || this.IsDeleted(ent))
   {
      // Don't try to update entities marked deleted,
      // even if they appear dirty via the default algorithm.
      // Seems like an NHibernate bug that it would consider it for update ...

      return new int[0];
   }

   return null;
}

However, assuming you haven't gone to the same trouble to track those status values, I don't know how else it can be dealt with. I'd submit a JIRA issue ...

Mare · **Joined:** Mon Nov 19, 2007 6:43 am **Posts:** 6

YoU assumed right :-) what is JIRA

Nels_P_Olsen · **Posted:** Wed Dec 05, 2007 12:35 pm

JIRA is the issue tracking system that NHibernate uses. Here is the link:
http://jira.nhibernate.org/secure/Dashboard.jspa

Tomaz · **Joined:** Tue Oct 11, 2005 8:02 am **Posts:** 6

Mare,

I've just made a small example with two tables - Orders and OrderDetails. Orders has a Set of OrderDetails, and OrderDetails has a many-to-one element associated with Orders table. All fields don't allow nulls.

Everything works OK - I load Orders entity, remove one OrderDetails element from Orders' Set and NHibernate produces only one Delete Sql command. The OrderDetails Set defined in HBM for Orders entity has cascade="all-delete-orphan" so maybe check the value in the cascade tag.

If this wouldn't help please post both HBM files. Here are HBM files for the example described above:

Code:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" default-lazy="false">
<class name="OrdersEntity, Aaa.Server.Data" table="Orders">
  <id name="Id" column="IdOrder" type="System.Int32"unsaved-value="null"><generator class="native"/></id>
  <property name="Name"  column="Name" type="System.String" not-null="true" length="50"/>
  <set name="OrderDetailsSet"
    cascade="all-delete-orphan"
    inverse="true"
    lazy="true">
    <key column="IdOrder"/>
    <one-to-many class="OrderDetailsEntity, Aaa.Server.Data"/>
  </set>
</class>
</hibernate-mapping>

Code:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" default-lazy="false">
<class name="OrderDetailsEntity, Aaa.Server.Data" table="OrderDetails">
  <id name="Id" column="IdOrderDetail" type="System.Int32" unsaved-value="null"><generator class="native"/></id>
  <property name="Amount"  column="Amount" type="System.Double" not-null="true" />                               
  <many-to-one name="Order" column="IdOrder" not-null="true" outer-join="auto"></many-to-one>
</class>
</hibernate-mapping>

Mare · **Joined:** Mon Nov 19, 2007 6:43 am **Posts:** 6

Tomas,

Tenx for answer. I found the reason: inside set tag I was missing inverse property set to true..
I added that (in parent's hbm) and it work as U described.

No JIRA issue needed :-)

regards