Custom #Query in JPA - mysql

I am trying to do a #Query in JPA that does not return a Entity from my Model.
In my Model I have BudgetPlan, BudgetGeschaftsfeld, BudgetMarke, BudgetKampagne, BudgetBucket, Kosten Entities which have a #OneToMany relationship.
So Budgetplan has many BudgetGeschaftsfeld which has many BudgetMarke and so on.
I want to return a CustomKosten with all couple of the standard Kosten attributes, and the ID to each "Parent ID". A Pojo of the Class would look like this.
#Getter
#Setter
#NoArgsConstructor
#AllArgsConstructor
#ToString
public class CustomKosten {
private long id;
private String name;
private double betrag;
private String status;
private Date local_date;
private long idBucket;
private String bucket;
private long idKampagne;
private String kampagne;
private long idMarke;
private String marke;
private long idGeschaeftsfeld;
private String geschaeftsfeld;
private long idPlan;
private String plan;
}
I have accomplished the SQL query in MySQL and it gets the result I want. Which looks like this.
public interface CustomKostenRepository extends JpaRepository<CustomKosten, Long> {
#Query(nativeQuery = true, value="select id, name, betrag, status, local_date, idbucket, bucket, idkampagne, kampagne, idmarke, marke, idgeschaeftsfeld, geschaeftsfeld, idplan, plan from \r\n"
+ "(select * from (select * from (select * from (select * from (select pid as pidgeschaeftsfeld, id as idgeschaeftsfeld, name as geschaeftsfeld from budman_db.budget where dtype=\"Budgetgeschaftsfeld\") as tgeschaeftsfeld \r\n"
+ "left join (select id as idplan, name as plan from budman_db.budget where dtype=\"Budgetplan\" ) as tplan on tgeschaeftsfeld.pidgeschaeftsfeld= tplan.idplan) as t1\r\n"
+ "left join (select pid as pidmarke, id as idmarke, name as marke from budman_db.budget where dtype=\"Budgetmarke\") as tmarke on t1.idgeschaeftsfeld= tmarke.pidmarke) as t2\r\n"
+ "Left join (select pid as pidkampagne, id as idkampagne, name as kampagne from budman_db.budget where dtype=\"Budgetkampagne\") as tkampagne on t2.idmarke= tkampagne.pidkampagne ) as t3\r\n"
+ "left join (select pid as pidbucket, id as idbucket, name as bucket from budman_db.budget where dtype=\"Budgetbucket\") as tbucket on t3.idkampagne= tbucket.pidbucket) as t4\r\n"
+ "left join (select * from budman_db.kosten ) as tkosten on t4.idbucket= tkosten.pid")
public List<CustomKosten> getCustomKostenKomplex();
}
is the result I'm trying to get even possible?
I am getting this Error when running my code.
Any advice is much appreciated
Caused by: java.lang.IllegalArgumentException: Not a managed type: class com.bm.ent.kosten.CustomKosten
Edit:
After following the Example Eugene adviced im getting another error.
Caused by: java.lang.IllegalArgumentException: Could not locate appropriate
constructor on class : com.bm.ent.kosten.CustomKosten
I'm guessing it has something to do with the Type of each field. And I think I don't have to put a type on those which have a primitive class.
note: I purposely left out the date to test. Any advice?
#Entity(name= "Kosten")
#Table(name= "kosten")
#NamedNativeQuery(name = "CustomKostenAll",
query= "select id, name, betrag, status, idbucket, bucket, idkampagne, kampagne, idmarke, marke, idgeschaeftsfeld, geschaeftsfeld, idplan, plan from \r\n"
+ "(select * from (select * from (select * from (select * from (select pid as pidgeschaeftsfeld, id as idgeschaeftsfeld, name as geschaeftsfeld from budman_db.budget where dtype=\"Budgetgeschaftsfeld\") as tgeschaeftsfeld \r\n"
+ "left join (select id as idplan, name as plan from budman_db.budget where dtype=\"Budgetplan\" ) as tplan on tgeschaeftsfeld.pidgeschaeftsfeld= tplan.idplan) as t1\r\n"
+ "left join (select pid as pidmarke, id as idmarke, name as marke from budman_db.budget where dtype=\"Budgetmarke\") as tmarke on t1.idgeschaeftsfeld= tmarke.pidmarke) as t2\r\n"
+ "left join (select pid as pidkampagne, id as idkampagne, name as kampagne from budman_db.budget where dtype=\"Budgetkampagne\") as tkampagne on t2.idmarke= tkampagne.pidkampagne ) as t3\r\n"
+ "left join (select pid as pidbucket, id as idbucket, name as bucket from budman_db.budget where dtype=\"Budgetbucket\") as tbucket on t3.idkampagne= tbucket.pidbucket) as t4\r\n"
+ "left join (select * from budman_db.kosten ) as tkosten on t4.idbucket= tkosten.pid",
resultSetMapping= "CustomKostenMapping")
#SqlResultSetMapping(name = "CustomKostenMapping",
classes = {
#ConstructorResult(targetClass = CustomKosten.class,
columns = {
#ColumnResult(name = "id"),
#ColumnResult(name = "name", type = String.class),
#ColumnResult(name = "betrag"),
#ColumnResult(name = "status", type = Status.class),
// #ColumnResult(name = "local_date"),
#ColumnResult(name = "idbucket"),
#ColumnResult(name = "bucket", type = String.class),
#ColumnResult(name = "idkampagne"),
#ColumnResult(name = "kampagne", type = String.class),
#ColumnResult(name = "idmarke"),
#ColumnResult(name = "marke", type = String.class),
#ColumnResult(name = "idgeschaeftsfeld"),
#ColumnResult(name = "geschaeftsfeld", type = String.class),
#ColumnResult(name = "idplan"),
#ColumnResult(name = "plan", type = String.class),
}
)
})
#Getter
#Setter
#NoArgsConstructor
public class Kosten {...}


First, if you want to use the CustomKosten class as return type of your repository, you need to place annotate it with #Entity so that it becomes a managed type for JPA / Hibernate.
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