Error dehydrating property value for class

Question

I am trying to insert a object but it throwns me the Error: dehydrating property value for FrancosPoS.DBMapping.order.obs

I've looked here for

NHibernate: Error dehydrating property - What the heck is this? ,

NHibernate - Error dehydrating property value and

Receiving Index Out of Range with NHibernate, but none of them worked.

I have checked and re-checked my mapping to multiple columns declarations but did not find any problem.

My clue is that the problem has something to do with the bigint on the MySQL database and the identity generator. When I change it to increment the dehydrating error goes away and the Index out of range exception appears.

Additionally, this is happening on the Session Save call. With the increment generator, the error happens at commit time.

Here is my order xml mapping:

<?xml version="1.0" encoding="utf-8"?>
<hibernate-mapping assembly="FrancosPoS" namespace="FrancosPoS.DBMapping" xmlns="urn:nhibernate-mapping-2.2">
<class name="order" table="`order`" lazy="true" >
<id name="idOrder">
  <generator class="identity" />
</id>
<many-to-one lazy="false" name="employee">
  <column name="idEmployee" sql-type="bigint(20)" not-null="false" />
</many-to-one>
<many-to-one lazy="false" name="customer">
  <column name="idCustomer" sql-type="bigint(20)" not-null="false" />
</many-to-one>
<many-to-one lazy="false" name="address">
  <column name="idAddress" sql-type="bigint(20)" not-null="false" />
</many-to-one>
<property name="date">
  <column name="date" sql-type="datetime" not-null="true" />
</property>
<property name="bakingTime">
  <column name="date" sql-type="datetime" not-null="false" />
</property>
<property name="price">
  <column name="price" sql-type="decimal(8,4)" not-null="true" />
</property>
<property name="cash">
  <column name="cash" sql-type="tinyint(1)" not-null="false" />
</property>
<property name="credit">
  <column name="credit" sql-type="tinyint(1)" not-null="false" />
</property>
<property name="houseNumber">
  <column name="houseNumber" sql-type="bigint(20)" not-null="false" />
</property>
<property name="complement">
  <column name="complement" sql-type="bigint(20)" not-null="false" />
</property>
<property name="obs">
  <column name="obs" sql-type="varchar(350)" not-null="false" />
</property>

<bag name="orderPsi" table="ordPsi" cascade="all" inverse="true">
      <key column="idOrdPastaI" />
      <one-to-many class="ordPsi" />
</bag>
</class>
</hibernate-mapping>

And the cs class:

public partial class order {
    public order() { }
    public virtual long idOrder { get; set; }
    public virtual employee employee { get; set; }
    public virtual customer customer { get; set; }
    public virtual address address { get; set; }
    public virtual System.DateTime date { get; set; }
    public virtual System.Nullable<System.DateTime> bakingTime { get; set; }
    public virtual string price { get; set; }
    public virtual System.Nullable<int> cash { get; set; }
    public virtual System.Nullable<int> credit { get; set; }
    public virtual System.Nullable<long> houseNumber { get; set; }
    public virtual System.Nullable<long> complement { get; set; }
    public virtual string obs { get; set; }
    public virtual IList<ordPsi> orderPsi { get; set; }
}

Here is the inner exception followed by the stack trace:

"Parameter index is out of range."
at MySql.Data.MySqlClient.MySqlParameterCollection.CheckIndex(Int32 index)
at MySql.Data.MySqlClient.MySqlParameterCollection.GetParameter(Int32 index)
at System.Data.Common.DbParameterCollection.System.Collections.IList.get_Item(Int32 index)
at NHibernate.Type.NullableType.NullSafeSet(IDbCommand cmd, Object value, Int32 index)
at NHibernate.Type.NullableType.NullSafeSet(IDbCommand st, Object value, Int32 index, Boolean[] settable, ISessionImplementor session)
at NHibernate.Persister.Entity.AbstractEntityPersister.Dehydrate(Object id, Object[] fields, Object rowId, Boolean[] includeProperty, Boolean[][] includeColumns, Int32 table, IDbCommand statement, ISessionImplementor session, Int32 index)

score 3 · Accepted Answer · answered Nov 24 '12 at 21:44

I have found the solution by trial and error, commenting all the mappings on the xml file that could be null in the database and I've got stuck in the bakingTime property:

<property name="bakingTime">
  <column name="date" sql-type="datetime" not-null="false" />
</property>

As I guessed (and others suggested on the other posts) the mapping is wrong. By a copy-paste problem [:P] the column name of bakingTime refers to the date column, not to itself!!!

So, this should be:

<property name="bakingTime">
  <column name="bakingTime" sql-type="datetime" not-null="false" />
</property>

Also, this post is still valuable, even though is not so new:

"NHibernate Nullable DateTime Issues - Ayende"

I've made the very same mistake. I mapped two different properties to the same field in DB and as a result got many strange 'Error dehydrating property' errors (with 'Index was out of range' and 'Specified cast is not valid' inside) on different properties but not on that where the problem was. So it took me a while to found the real source of my problems. — Ilya Serbis, Feb 03 '14 at 13:05

score 1 · Answer 2 · answered Nov 24 '12 at 13:34

1

Funny naming scheme for .Net code, but you shouldn't need both <id> and <property> for idOrder.

answered Nov 24 '12 at 13:34

Oskar Berggren

5,583
1
19
36

I see. It was not before, I just tried to use to see if this would help. I will edit the post to remove. Thanks. – gbc921 Nov 24 '12 at 21:01

Error dehydrating property value for class

2 Answers2