Problem with NHibernate:Unexpected row count: 0; expected: 1

Question

I have two tables:

DIC_STATUS:

STATUS_ID

   1
   2

DIC_STATUS_STRINGS:

STATUS_ID   LANG_ID   STATUS_NAME

    1         1         Name1
    1         2         Name1_1
    2         1         Name2
    2         2         Name2_2

And classes:

public class StatusS : AbstractDictionaryObject
    {
        public virtual string StatusName { get; set; }
        public virtual Languages Lang { get; set; }
        public virtual Status Status { get; set; }
    }

  public class Status:AbstractDisplayDictionary
    {
        [Browsable(false)]
        public IList<StatusS> DicStatusStrings { get; set; }
        public Status()
        {
            DicStatusStrings = new List<StatusS>();
        }
    }

 public abstract class AbstractDisplayDictionary
    {
        [Browsable(false)]
        public virtual int Id { get; set; }
        [DisplayName("Наименование на русском")]
        public virtual string NameRu { get; set; }
        [DisplayName("Наименование на казахском")]
        public virtual string NameKz { get; set; }
    }

Mapping files:

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="EArchive.Data" namespace="EArchive.Data.Class">  
  <class name="Status" table="DIC_STATUS" lazy="false">
    <id name="Id" column="STATUS_ID">
      <generator class="increment">
      </generator>
    </id>
    <bag name="DicStatusStrings" inverse="true" cascade="all-delete-orphan">
      <key column="STATUS_ID" />
      <one-to-many class="StatusS" />
    </bag>
    <property name="NameRu"
              formula="(SELECT str.STATUS_NAME FROM DIC_STATUS_STRINGS str
              WHERE str.Status_Id = Status_Id and str.Lang_Id=1)"/>

    <property name="NameKz"
              formula="(SELECT str.STATUS_NAME FROM DIC_STATUS_STRINGS str
              WHERE str.Status_Id = Status_Id and str.Lang_Id=2)"/>    
  </class>
</hibernate-mapping>

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="EArchive.Data" namespace="EArchive.Data.Class">
<class name="StatusS" table="DIC_STATUS_STRINGS" lazy="false">
  <composite-id>    
    <key-many-to-one name="Status" class="Status">
      <column name="STATUS_ID"/>
    </key-many-to-one>
    <key-property name="LangId" column="LANG_ID"/>
  </composite-id>
  <property name="StatusName" column="STATUS_NAME"/>
  <many-to-one name="Lang" class="Languages" column="LANG_ID" />  
</class>
</hibernate-mapping>

Method to add record:

 public void AddRecord(object record)
        {
            StatusDAO statusDao = GetStatusDAO();
            var status = (Status) record;
            IList<StatusS> statusS = status.DicStatusStrings;
            status.DicStatusStrings = null;
            status = statusDao.Save(status);

            foreach (var s in statusS)
            {
                s.Status = status;
            }
            status.DicStatusStrings = statusS;
            statusDao.Update(status);
        }

I have error only for adding record, editing works well. Thanks.

EDIT: The Equals and GetHashCode methods is overriden.

It could be a DB trigger causing this. See here: http://stackoverflow.com/questions/821981/nhibernate-updating-a-table-with-a-trigger-on-it-causes-an-error-unexpected — user2173353, Mar 20 '14 at 12:45

score 1 · Answer 1 · edited May 23 '17 at 10:34

1

I had the same problem with composite keys. It's related to the Equals() and GetHashCode().

You have to override those, otherwise NHibernate can't know the difference between them.

Have a look here and here for more information.

EDIT: It's actually related to the match between saved and unsaved objects. Missing overrides of Equals and GetHashCode is one of multiple thing which can cause this.

edited May 23 '17 at 10:34

Community

1
1

answered Aug 10 '11 at 12:01

Jonas Stensved

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:I did it, just not written in question. – user348173 Aug 10 '11 at 12:09
I noticed inverse="true" on Status.DicStatusStrings. It makes the other side responsible for the relation which might prevent it from getting set if you call update on Status. – Jonas Stensved Aug 10 '11 at 13:27
Look at [this thread](https://forum.hibernate.org/viewtopic.php?p=2369496) (the 4th post from the top by "ibaf31"). It suggests using and explains why. – Jonas Stensved Aug 11 '11 at 06:48
thanks for link, but I saw it. If I changed to native then throwing following exception: "Cannot insert the value NULL into column 'STATUS_ID', table 'EArchive.dbo.DIC_STATUS'; column does not allow nulls. INSERT fails. The statement has been terminated." in the line: status = statusDao.Save(status);. I have trying add unsaved-value but not works. – user348173 Aug 11 '11 at 09:20
Hmm. Do you have the inverse="true" attribute? Add it if not. This error looks like the other end of the relation is being saved before Status has and ID generated. – Jonas Stensved Aug 11 '11 at 09:48
Yes, I have it. – user348173 Aug 11 '11 at 10:12

Problem with NHibernate:Unexpected row count: 0; expected: 1

1 Answers1