public class Search
    {
        public virtual string SearchedWords { get; set; }
        public virtual int SearchId { get; protected set; }
        public virtual int AudioId { get; set; }

        public Search() {}

        public Search(int audioid, string words)
        {
            SearchedWords = words;
            AudioId = audioid;
        }
    }

    public class AudioFile
    {
        public virtual string FullPath { get; set; }
        public virtual int Id { get; protected set; }
        public virtual IList<Search> Searches { get; set; }

        public AudioFile() { }
        
        public AudioFile(string file)
        {
            FullPath = file;
        }
    }

/****** Object:  Table [dbo].[AudioFiles]    Script Date: 04/20/2010 17:43:06 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[AudioFiles](
	[audioId] [int] IDENTITY( 1 , 1 ) NOT NULL,
	[fullPath] [text] NULL,
 CONSTRAINT [PK_AudioFiles] PRIMARY KEY CLUSTERED 
(
	[audioId] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
/****** Object:  Table [dbo].[Searches]    Script Date: 04/20/2010 17:43:06 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Searches](
	[searchId] [int] IDENTITY( 1 , 1 ) NOT NULL,
	[wordsForSearch] [text] NULL,
	[audioId] [int] NULL
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
/****** Object:  ForeignKey [FK_Searches_AudioFiles]    Script Date: 04/20/2010 17:43:06 ******/
ALTER TABLE [dbo].[Searches]  WITH CHECK ADD  CONSTRAINT [FK_Searches_AudioFiles] FOREIGN KEY([audioId])
REFERENCES [dbo].[AudioFiles] ([audioId])
GO
ALTER TABLE [dbo].[Searches] CHECK CONSTRAINT [FK_Searches_AudioFiles]
GO

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"  namespace="Data" assembly="BusinessLayer">
  <class name="Search" table="Searches" lazy="false">
    <id name="SearchId">
      <column name="searchId" not-null="false"/>
      <generator class="native"/>
    </id>
    <property name="SearchedWords" column="wordsForSearch"/>
  </class>
</hibernate-mapping>

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="Data" assembly="BusinessLayer">
  <class name="AudioFile" table="AudioFiles">
    <id name="Id" unsaved-value="0">
      <column name="audioId" not-null="true" unique="true" unique-key="PK_AudioFiles"/>
      <generator class="identity"/>
    </id>
    <property name="FullPath" column="fullPath"/>
    <many-to-one name="Searches" class="Search" column="audioId"/>
  </class>
</hibernate-mapping>