Hi,

I have a unique key constraint on a table named as suppose Employee, this key is made of using two columns(suppose Name& Join_date) in same table, can we create this unique key constraint using hbm/pojo in hibernate also for saving purpose. Currently I am just looking up object for unique key fields using criteria api and comparing in at java side and then saving if object not exist otherwise ignoring it, is there no way so that hibernate can directly check for unique key by making some changes in hbm or pojo.
If there is any other solution for it, Can anyone please suggest what changes need in hbm and pojo for this.


Thanks,
Sachin Panwar

Here I am gettign unique key constraint error when trying to save other object with same unique Key, is there any way that we can set unique key with multiple columns in hbm/pojo file so that it can directly check for a unique key and ignore to save the object if key exist already..
I am trying it jut by lookup the object with unique key before saving it to DB and comparing if object with same values exits , I am ignoringing it otherwise saving it.

Thanks,
Sachin Panwar

Can Anyone help me out here..

Hi Sachin,
I know it's quite late to reply, and maybe you found a solution yet.
I'm facing the same problem: how to create unique indexes on multiple columns in mapping files.
I found the tag "properties" and applied my usual learn-by-doing approach. Actually it does what you think: create a [unique] index on the columns listed inside.
So, I went on with my project but there is a problem: Hibernate goes mad with aliases if they refer to the child properties of the tag "properties".
To explain, this is the mapping example I made (a simple localization labels storage):

but when I try to fetch LabelText objects I get an "Unknown column: alias_0x1_.language" error.

Is there anybody who has another solution?

Thanks,
Stefano