Bi-directional List not re-ordering and duplicated position

smallufo · **Posted:** Fri Sep 19, 2008 12:13 pm

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Hibernate version: hibernate-3.2.5

Mapping documents:

Code:

  <class name="Account">
    <list name="albums" cascade="save-update" inverse="false">
      <cache usage="nonstrict-read-write"/>
      <key column="accountId" not-null="true" update="false"/>
      <list-index column="position"/>
      <one-to-many class="Album"/>
    </list>
  </class>

  <class name="Album">
    <cache usage="nonstrict-read-write"/>
    <id name="id" column="id" type="int">
      <generator class="increment"/>
    </id>
    <many-to-one name="account" column="accountId" not-null="true" insert="false" update="false"/>
  </class>

This is my mapping file
An account has a list of Album
When an album is deleted , the POSITION column is not re-ordering.
When an new Album is inserted , the POSITION value will equal the max.

If Account acc has Albums 0,1,2,3
If album0 is removed , the POSITION is still 1,2,3 (not 0,1,2)
If a new album is appended , the POSITION becomes 1,2,3,3
"3" is duplicated !!!

It seems the problem has been proposed many times , different people have different setting , but I cannot find a working solution...

Can some body help me ! thank you very much....

gonzao_diaz · **Joined:** Mon Nov 26, 2007 2:29 pm **Posts:** 443

smallufo,

This feature is still somewhat confusing to implement, as of Hibernate 3.2.2.
And the documentation doesn't help much.

But coincidentally, I wrote an article with an example very similar to your Account-Albums case. Mine is Singer-Albums, and it presents a complete example on how to implement a bidirectional list.
Check it out and tell me what you think.

gonzao_diaz · **Joined:** Mon Nov 26, 2007 2:29 pm **Posts:** 443

sorry, double post :)

smallufo · **Posted:** Sat Sep 20, 2008 4:22 am

gonzao_diaz wrote:

smallufo,

This feature is still somewhat confusing to implement, as of Hibernate 3.2.2.
And the documentation doesn't help much.

But coincidentally, I wrote an article with an example very similar to your Account-Albums case. Mine is Singer-Albums, and it presents a complete example on how to implement a bidirectional list.
Check it out and tell me what you think.

Hi
Your config is almose the same with mime ... except :

Code:

Yours :
<list name="albums" lazy="true" cascade="all">

Code:

Mine :
<list name="albums" cascade="save-update" inverse="false">

I didn't append "delete" or "delete-orphan" to cascade , because I want to manually delete a album.

Code:

Yours :
<key column="SINGER_ID" not-null="true"/>

Code:

Mine:
<key column="accountId" not-null="true" update="false"/>

I have an additional update="false" attribute here.
I am not sure what it is here , I saw many posts/configs with it.

Is your code able to successfully re-order the POSITION here ?

smallufo · **Posted:** Sat Sep 20, 2008 5:04 am

I try to remove update="false"
<key column="accountId" not-null="true" update="false"/>
becomes :
<key column="accountId" not-null="true"/>

It worked!
The list POSITION can be successfully re-ordered.

BUT , every time I insert a list of objects , I noticed Hibernate first insert and then update...
If I insert 100 albums , there will be 200 SQL commands executed.
I feel this is a very redundent SQL command (and time comsuming)...
Is there any way to prevent this ?

l0s · **Joined:** Tue Jan 22, 2008 10:10 pm **Posts:** 1

gonzao_diaz wrote:

But coincidentally, I wrote an article with an example very similar to your Account-Albums case. Mine is Singer-Albums, and it presents a complete example on how to implement a bidirectional list.
Check it out and tell me what you think.

gonzao_diaz, I get a 404 on the link you provided. Although after a bit of poking around, I think the proper url is http://hibernar.org/articulos_en/bidire ... _lists.php