order-by

zubra_bubra · **Joined:** Fri Mar 03, 2006 6:49 am **Posts:** 3

Hi, all! (I am a newbie for Hibernate)

look in hibernate reference
order-by (optional, JDK1.4 only) specify a table column (or columns) that define the iteration order of
the Map, Set or bag, together with an optional asc or desc

at test/org.hibernate.test.collection

in UserPermissions.hbm.xml:

Code:

      <map name="sessionData" 

            order-by="lower(`attributeName`) asc"

            lazy="extra">
         <key column="userName"/>
         <map-key column="`attributeName`" 
               type="string"/>
         <element column="`attributeValue`" 
               type="serializable" 
               not-null="true"/>
      </map>

There we have ordering by lower(column_name).

What is correct?
Does somebody know workaround in case my DB supports only

Code:

order by column_name asc|desc

?

kochcp · **Posted:** Fri Mar 03, 2006 11:28 am

not entirely sure what you're asking..

are you asking what if the underlying DB doesn't support having the 'lower' command after the words 'order by'?

I would say the easiest way is to simply change the mapping files on a case by case basis. The beauty of having this stuff in xml files is that it doesn't require recompiling the project to implement a change... unless you're using WAR or JAR files :)

zubra_bubra · **Joined:** Fri Mar 03, 2006 6:49 am **Posts:** 3

kochcp wrote:

not entirely sure what you're asking..

are you asking what if the underlying DB doesn't support having the 'lower' command after the words 'order by'?

Thank you.

I will try to explain more clearly.

Really I find this example in test directory of hibernate (downloaded from CVS), so it's strange for me tests doesnt satisfy to reference.

I test my dialect for Hibernate.
Most of tests passed. But some not. I start to research what was wrong, and in org.hibernate.test.collection.CollectionTest find mapping file that doesnt correct (order-by allowed only by column(s), not by expression as in hibernate_reference.pdf).

Code:

order-by="lower(`attributeName`) asc"

in reference of Hibernate we have possibility to order by column(s) only, not by expression. (May be I have missed something in hibernate_reference.pdf?)

kochcp · **Posted:** Fri Mar 03, 2006 11:54 am

well, I don't know what to tell ya. Guess it isn't supported by your database

zubra_bubra · **Joined:** Fri Mar 03, 2006 6:49 am **Posts:** 3

Just forget about DB (really DB doesnt support it!).

In test (written by Gavin King) we have error in hbm file.

map::order-by = "lower(`attributeName`) asc", and if you open HibRef you see order-by = "column[, columns] asc|desc".

Who can help me to clarify is it mistake or not?