<hibernate-mapping default-cascade="save-update">

    <class name="<my-path>.Album" table="albums">
       
      <id name="albumId" type="long">
        <column name="album_id"/>
        <generator class="sequence">
        <param name="sequence">album_id</param>
      </generator>
      </id>

      <!-- <SNIP> PROPERTIES -->

      <list name="tracks" table="album_tracks" lazy="true" cascade="save-update,delete, delete-orphan">
        <key column="album_id"/>
       <list-index column="track_position"/>
         <many-to-many class="<my-path>.Track" column="track_id"/>
        </list>

    </class>

</hibernate-mapping>

<hibernate-mapping>

   <hibernate-mapping>

    <class name="com.mediagraft.podsplice.domain.Track" table="tracks">
       
        <id name="trackId" type="long">
            <column name="track_id"/>
            <generator class="sequence">
            <param name="sequence">track_id</param>
         </generator>
        </id>

      
        <join table="album_tracks"
              inverse="true"
              optional="true">
          <key column="track_id"/>
          <many-to-one name="album"
                       column="album_id"
                       not-null="true"/>
        </join>
      
        <!-- <SNIP> PROPERTIES -->

    </class>

</hibernate-mapping>

-- Albums

CREATE TABLE albums (
    album_id          BIGINT NOT NULL,       -- Album ID generated from sequence
    title                  VARCHAR(50),           -- title of album
    description        VARCHAR(500),          -- description of album
    date                 TIMESTAMP,             -- when album info was last updated
    artist_id            BIGINT NOT NULL,       -- any artist info
    composer_id     BIGINT NOT NULL,       -- any composer info

    PRIMARY KEY(album_id),
    CONSTRAINT albums_unique_album UNIQUE(title, artist_id),
    CONSTRAINT albums_fkey_artist_id FOREIGN KEY(artist_id) REFERENCES artists ON DELETE CASCADE,
    CONSTRAINT albums_fkey_composer_id FOREIGN KEY(composer_id) REFERENCES composers ON DELETE CASCADE
) WITHOUT OIDS;

-- Tracks

CREATE TABLE tracks (
    track_id             BIGINT NOT NULL,       -- ID of music track generated from sequence
    track_number         SMALLINT NOT NULL,     -- track number
    title                VARCHAR(50),           -- title of music track
    description          VARCHAR(500),          -- description of music track
    duration             BIGINT,                -- duration of music track in seconds
    genre_id             BIGINT NOT NULL,       -- id of genre
    artist_id            BIGINT NOT NULL,       -- any artist info
    composer_id          BIGINT NOT NULL,       -- any composer info
    date                 TIMESTAMP,             -- when track was last updated
    file_location        VARCHAR(300) NOT NULL, -- location of associated file

    PRIMARY KEY(track_id),
    CONSTRAINT tracks_fkey_genre_id FOREIGN KEY(genre_id) REFERENCES genres ON DELETE CASCADE,
    CONSTRAINT tracks_fkey_artist_id FOREIGN KEY(artist_id) REFERENCES artists ON DELETE CASCADE,
    CONSTRAINT tracks_fkey_composer_id FOREIGN KEY(composer_id) REFERENCES composers ON DELETE CASCADE
) WITHOUT OIDS;

-- Albums to tracks

CREATE TABLE album_tracks (
    album_id             BIGINT NOT NULL,       -- album ID
    track_id             BIGINT NOT NULL,       -- track ID
    track_position       INTEGER NOT NULL,      -- position of track on album

    UNIQUE(track_id),                 -- ensure tracks can only belong to one album
    CONSTRAINT album_tracks_fkey_album_id FOREIGN KEY(album_id) REFERENCES albums ON DELETE CASCADE,
    CONSTRAINT album_tracks_fkey_track_id FOREIGN KEY(track_id) REFERENCES tracks ON DELETE CASCADE
) WITHOUT OIDS;

<class name="Person">
    <id name="id" column="personId">
        <generator class="native"/>
    </id>
    <set name="addresses"
        table="PersonAddress">
        <key column="personId"/>
        <many-to-many column="addressId"
            unique="true"
            class="Address"/>
    </set>
</class>

<class name="Address">
    <id name="id" column="addressId">
        <generator class="native"/>
    </id>
    <join table="PersonAddress"
        inverse="true"
        optional="true">
        <key column="addressId"/>
        <many-to-one name="person"
            column="personId"
            not-null="true"/>
    </join>
</class>

create table Person ( personId bigint not null primary key )
create table PersonAddress ( personId bigint not null, addressId bigint not null primary key )
create table Address ( addressId bigint not null primary key )