Question

I am trying to convert a native SQL query to use the Criteria API in JPA 2.0. I have found a lot of Criteria API examples on Google, but I am having a really hard time putting all of the pieces together. I’m hoping that a more experienced person will be able to help me out. The native query looks like this:

select 
    sum(amount) from firstTable, secondTable 
        where firstTable.id = secondTable.id 
            and amount <> 0 
            and firstTable.id = ?
union all
select 
    sum(amount) from firstTable, thirdTable 
        where firstTable.id = thirdTable.id 
            and amount <> 0 
            and firstTable.id = ?

The original query result set was returning a List of BigDecimal objects.

Thank you!

Answer 1

JPA does not support UNION, either use a native SQL query, or execute two queries.