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Criteria across multiple tables

David Zazeky

Joined: Nov 05, 2008
Posts: 7

I have a legacy database with two tables: Logs and ArchivedLogs. They have identical schemas (LogID, Message, TimePosted, etc...). I have a separate HBM mapping file and Java class for both tables. I'm trying to use Criteria to search both tables and return a single list of results, but I'm having trouble getting the correct syntax. Here is what I tried so far:

Criteria theSearch = getHibernateTemplate().getSessionFactory().getCurrentSession().createCriteria(Logs.class);
theSearch.add("TimePosted", timeValue));
return theSearch.list();

The problem with the above code is that it only searches the Logs table. I could separately run the criteria on ArchivedLogs, but the results wouldn't be sorted properly between the two tables.

So I have two questions:

1. Is there any way in Hibernate to map two tables with identical schemas to the same POJO object?

2. If not, can I use a Criteria query to return results from both POJO objects (one per table)? If so, how? Would using plain HQL be a better option?


I agree. Here's the link:
subject: Criteria across multiple tables
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