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POWhy one-to-many does not work as expected in NHibernate?
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I have very simple situation and really don't have a clue why this isn't working. This is my schema: <pre><code>**[item]** id (PK) symbol **[item_version]** id (PK) item_id (FK->ITEM) symbol </code></pre> These are my mappings: item.hbm.xml <pre><code><class name="Core.Model.Entities.Item, Core.Model" table="item" lazy="false"> <id name="Id" column="id" type="long"> <generator class="native" /> </id> <property name="Symbol" column="symbol"/> <bag name="ItemVersions" lazy="false" table="item_version" inverse="true" cascade="save-update"> <key column="item_id" /> <one-to-many class="Core.Model.Entities.ItemVersion, Core.Model"/> </bag> </class> </code></pre> *item_version.hbm.xml* <pre><code><class name="Core.Model.Entities.ItemVersion, Core.Model" table="item_version" lazy="false"> <id name="Id" column="id" type="long"> <generator class="native" /> </id> <many-to-one name="Item" class="Core.Model.Entities.Item, Core.Model" column="item_id" cascade="save-update"/> <property name="Symbol" column="symbol"/> </class> </code></pre> These are the classes: Item.cs <pre><code>public class Item : Entity<IItemDao> { private long id; virtual public long Id { get { return this.id; } set { this.id = value; } } private string symbol; virtual public string Symbol { get { return this.symbol; } set { this.symbol = value; } } private IList<ItemVersion> item_versions = new List<ItemVersion>(); virtual public IList<ItemVersion> ItemVersions { get { return this.item_versions; } set { this.item_versions = value; } } } </code></pre> ItemVersion.cs <pre><code>public class ItemVersion : Entity<IItemVersionDao> { private long id; virtual public long Id { get { return this.id; } set { this.id = value; } } private Item item = null; virtual public Item Item { get { return this.item; } set { this.item = value; } } private long item_id = 0; virtual public long ItemId { get { return this.item_id; } set { this.item_id = value; } } private string symbol; virtual public string Symbol { get { return this.symbol; } set { this.symbol = value; } } } </code></pre> And this code... <pre><code>Item item = new Item(); item.Name = "test"; ItemVersion v = new ItemVersion(); v.Symbol = "test version"; item.ItemVersions.Add(v); Item.Dao.Save(tmp); </code></pre> ... does not work. It inserts an item and throws an exception while inserting item_version row, that item_version.item_id cannot be null. So item_id property isn't automatically set by NHibernate in ItemVersion object. Why cascade="save-update" and inverse="true" does not work in this case? When I set manually, by adding this code: <pre><code>v.Item = item; </code></pre> and than call save, everything works fine, but this is not what I except from NHibernate - calling <pre><code>item.ItemVersions.Add(v); </code></pre> should be sufficient. Am I doing something wrong or this is simply imposible? Thanks in advance for the answers :)
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<c#><.net><nhibernate><nhibernate-mapping>
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Why one-to-many does not work as expected in NHibernate?
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Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.