Getting select statement results from a stored procedure using JPA?

Question

Using JPA, I'm calling a MS SQL Server 2008 R2 stored procedure that looks like this

procedure [dbo].[testProc]
    @param1 varchar(max),
    @param2 datetime
as
begin
EXEC sessionProc

DECLARE @reportData varbinary(max)

EXEC aThirdPartyProc
     @reportData out,
     @parameter1 = @param1,
     @date = @param2

SELECT col1, col2
FROM fFunction(@reportData)

end

When trying to get the results from the select statement

StoredProcedureQuery q = em.createNamedStoredProcedureQuery("reportData");
q.setParameter("param1", "val1");
q.setParameter("param2", new Date());
return (List<ReportData>) q.getResultList();

I get

java.lang.IllegalStateException: Current CallableStatement ou was not a ResultSet, but getResultList was called
    at org.hibernate.jpa.internal.StoredProcedureQueryImpl.getResultList(StoredProcedureQueryImpl.java:319)

How can I get the select statement results?

Note: The JPA code works if I reduce testProc to a simple select (remove the two EXEC statements).

Also, here's the ReportData entity class:

@Entity
@NamedStoredProcedureQuery(name = "reportData", procedureName = "testProc", resultClasses = ReportData.class, parameters = {
        @StoredProcedureParameter(mode = ParameterMode.IN, name = "param1", type = String.class),
        @StoredProcedureParameter(mode = ParameterMode.IN, name = "param2", type = Date.class)
          })
public class ReportData {
    @Id
    private String col1;
    private String col2;
    // getter and setter for col1 and col2
}

I've tested the proc in SQL Server Management Studio and it works fine returning results from the select statement.

Answer 1

Feedback from multiple queries within SPs throw JPA off unless SET NOCOUNT ON; is used.

Insert SET NOCOUNT ON; after BEGIN in your SP.

Using SET NOCOUNT ON is a general best practice .

Answer 2

Introduce a parameter with mode = ParameterMode.REF_CURSOR and let your stored procedure return refcursor.

and then use

q.execute();
return (List<ReportData>) q.getResultList();

See here section Stored procedures with REF_CURSOR