check if a Map value exists

Dencel · **Joined:** Tue Jan 27, 2004 12:22 pm **Posts:** 103

How do you check if a Map value exists?

In the basic simple map situation (String index,String value), I used:

Code:

from obj o where o.map['key.to.check'] is not null

This works.

Now I have an object with a composite element:
Mapping

Code:

      <map name="variables" table="CUSTOMERVARIABLES" cascade="all" lazy="true" order-by="TIME_OF_CREATION" >
         <key column="ID"/>
         <index column="NAME" type="string"/>
         <composite-element class="nl.dennie.vikie.model.CustomerVariable">
            <property name="timeOfCreation" column="TIME_OF_CREATION" type="calendar"/>
            <property name="value" column="VALUE" type="string"/>
         </composite-element>
      </map>

The same check gives the following exception:
Exception

Code:

net.sf.hibernate.QueryException: path expression ended in composite collection element [from nl.dennie.vikie.model.Company c where c.variables['fetch.mail'] not is null]

Can somebody tell me how to do this? Or should I simply do an inner join on the map and check on it ?

Dencel · **Joined:** Tue Jan 27, 2004 12:22 pm **Posts:** 103

problem solved. I upgraded my database to support subselects.
I can now use:

Code:

from Obj o where 'key' in indices(o.map)

This is explained in chapter 11 of the Hibernate documentation.

Greetz