referencing java.util.map key in hql

bigor · **Joined:** Sat Feb 18, 2006 6:24 am **Posts:** 23

Hi,

I have object called Article which holds java.util.map property.

Map property is mapped like this:

Code:

<map name="translations" table="i18n_content" lazy="true">
         <key column="articleID" />
         <index column="language_code" type="string"/>
         <composite-element class="ArticleTranslation">
         
            <property name="title">
               <column name="k_title" length="255" not-null="true"/>
            </property>

Now, I want to query only those Article objects which have certain key in map.

I thought to solve this with join fetching using query like:

Code:

from Article as article 
    left join article.translations as translation 
        where .....

thats where I realized that I don't know how to reference to map key in HQL.
Can somebody help me about this problem? Is this even possible?

fdurden · **Joined:** Thu Nov 17, 2005 1:44 pm **Posts:** 6

Hi,

I've never found how/if this could be done. I've always had to do it with SQL directly. I don't know if there's a recently added feature allowing that though.

bigor · **Joined:** Sat Feb 18, 2006 6:24 am **Posts:** 23

fdurden wrote:

Hi,

I've never found how/if this could be done. I've always had to do it with SQL directly. I don't know if there's a recently added feature allowing that though.

Hmmm... somebody from Hibernate team? Any suggestions?

hibernate_user · **Joined:** Mon May 22, 2006 2:30 pm **Posts:** 74

If I understand what you are saying, you should be able to simply say something like "where translation.articleId = :articleId"

bigor · **Joined:** Sat Feb 18, 2006 6:24 am **Posts:** 23

hibernate_user wrote:

If I understand what you are saying, you should be able to simply say something like "where translation.articleId = :articleId"

More something like this: where article.translations.key = :languageCode
and article.translations.key should be replaced with reference to map key.
More I read HIbernate documentation more I believe that such thing is not possible :-(

kechow · **Joined:** Fri Dec 08, 2006 12:00 pm **Posts:** 1

bigor wrote:

Hi,
I thought to solve this with join fetching using query like:

Code:

from Article as article 
    left join article.translations as translation 
        where .....

thats where I realized that I don't know how to reference to map key in HQL.
Can somebody help me about this problem? Is this even possible?

You can try

Code:

from Article as article where :languageCode in indices(article.translations)

Hibernate will generate a subquery for the map index. See section 14.9 of the reference doc for more indexed collection fuctions.