HHH-17102 Fix @SqlResultSetMapping issue for joined inheritance entity result

hibernate-core/src/main/java/org/hibernate/boot/query/SqlResultSetMappingDescriptor.java

@@ -276,11 +276,7 @@ public class SqlResultSetMappingDescriptor implements NamedResultSetMappingDescr
 				String discriminatorColumn,
 				NavigablePath entityPath) {
 			final EntityDiscriminatorMapping discriminatorMapping = entityMapping.getDiscriminatorMapping();
-			if ( discriminatorMapping == null ) {
+			if ( discriminatorMapping == null || discriminatorColumn == null || !entityMapping.hasSubclasses() ) {
-				return null;
-			}
-
-			if ( discriminatorColumn == null ) {
 				return null;
 			}
 

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/internal/CaseStatementDiscriminatorMappingImpl.java

@@ -178,10 +178,10 @@ public class CaseStatementDiscriminatorMappingImpl extends AbstractDiscriminator
 
 	@Override
 	public String getContainingTableExpression() {
-		throw new UnsupportedOperationException();
+//		throw new UnsupportedOperationException();
 //		// this *should* only be used to create the sql-expression key, so just
 //		// using the primary table expr should be fine
-//		return entityDescriptor.getRootTableName();
+		return getEntityDescriptor().getMappedTableDetails().getTableName();
 	}
 
 	@Override

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/internal/ExplicitColumnDiscriminatorMappingImpl.java

@@ -14,11 +14,14 @@ import org.hibernate.metamodel.mapping.MappingType;
 import org.hibernate.spi.NavigablePath;
 import org.hibernate.sql.ast.spi.SqlAstCreationState;
 import org.hibernate.sql.ast.spi.SqlExpressionResolver;
+import org.hibernate.sql.ast.tree.expression.ColumnReference;
 import org.hibernate.sql.ast.tree.expression.Expression;
 import org.hibernate.sql.ast.tree.from.TableGroup;
 import org.hibernate.sql.ast.tree.from.TableReference;
 import org.hibernate.type.BasicType;
 
+import static org.hibernate.sql.ast.spi.SqlExpressionResolver.createColumnReferenceKey;
+
 /**
  * @author Steve Ebersole
  */
@@ -80,7 +83,15 @@ public class ExplicitColumnDiscriminatorMappingImpl extends AbstractDiscriminato
 			SqlAstCreationState creationState) {
 		final SqlExpressionResolver expressionResolver = creationState.getSqlExpressionResolver();
 		final TableReference tableReference = tableGroup.resolveTableReference( navigablePath, tableExpression );
-		return expressionResolver.resolveSqlExpression( tableReference, this );
+
+		return expressionResolver.resolveSqlExpression(
+				createColumnReferenceKey(
+						tableGroup.getPrimaryTableReference(),
+						getSelectionExpression(),
+						jdbcMappingToUse
+				),
+				processingState -> new ColumnReference( tableReference, this )
+		);
 	}
 
 	@Override

hibernate-core/src/main/java/org/hibernate/query/internal/ResultMementoEntityJpa.java

@@ -59,7 +59,7 @@ public class ResultMementoEntityJpa implements ResultMementoEntity, FetchMemento
 			ResultSetMappingResolutionContext context) {
 		final EntityDiscriminatorMapping discriminatorMapping = entityDescriptor.getDiscriminatorMapping();
 		final BasicValuedFetchBuilder discriminatorFetchBuilder;
-		if ( discriminatorMapping == null ) {
+		if ( discriminatorMapping == null || !entityDescriptor.hasSubclasses() ) {
 			assert discriminatorMemento == null;
 			discriminatorFetchBuilder = null;
 		}

hibernate-core/src/main/java/org/hibernate/query/results/complete/CompleteFetchBuilderBasicPart.java

@@ -13,7 +13,8 @@ import java.util.function.BiFunction;
 
 import org.hibernate.engine.FetchTiming;
 import org.hibernate.metamodel.mapping.BasicValuedModelPart;
-import org.hibernate.query.results.ResultsHelper;
+import org.hibernate.metamodel.mapping.DiscriminatorMapping;
+import org.hibernate.metamodel.mapping.JdbcMapping;
 import org.hibernate.spi.NavigablePath;
 import org.hibernate.query.results.BasicValuedFetchBuilder;
 import org.hibernate.query.results.DomainResultCreationStateImpl;
@@ -112,9 +113,17 @@ public class CompleteFetchBuilderBasicPart implements CompleteFetchBuilder, Basi
 
 		final int valuesArrayPosition = jdbcPositionToValuesArrayPosition( jdbcPosition );
 
+		final JdbcMapping jdbcMapping;
+		if ( referencedModelPart instanceof DiscriminatorMapping ) {
+			jdbcMapping = ( (DiscriminatorMapping) referencedModelPart ).getUnderlyingJdbcMapping();
+		}
+		else {
+			jdbcMapping = referencedModelPart.getJdbcMapping();
+		}
+
 		// we just care about the registration here.  The ModelPart will find it later
 		creationStateImpl.resolveSqlExpression(
-				createColumnReferenceKey( tableReference, referencedModelPart ),
+				createColumnReferenceKey( tableReference, referencedModelPart.getSelectablePath(), jdbcMapping ),
 				processingState -> new ResultSetMappingSqlSelection( valuesArrayPosition, referencedModelPart )
 		);
 

hibernate-core/src/main/java/org/hibernate/query/results/complete/CompleteResultBuilderEntityJpa.java

@@ -60,7 +60,7 @@ public class CompleteResultBuilderEntityJpa implements CompleteResultBuilderEnti
 		}
 		else {
 			// discriminated
-			assert discriminatorFetchBuilder != null;
+			assert !entityDescriptor.hasSubclasses() || discriminatorFetchBuilder != null;
 		}
 	}
 

hibernate-core/src/test/java/org/hibernate/orm/test/query/resultmapping/InheritanceTests.java

@@ -0,0 +1,156 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.orm.test.query.resultmapping;
+
+import java.util.List;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityResult;
+import jakarta.persistence.FieldResult;
+import jakarta.persistence.Id;
+import jakarta.persistence.Inheritance;
+import jakarta.persistence.InheritanceType;
+import jakarta.persistence.NamedNativeQuery;
+import jakarta.persistence.SqlResultSetMapping;
+import jakarta.persistence.Table;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+@DomainModel( annotatedClasses = {
+		InheritanceTests.Parent.class,
+		InheritanceTests.Child.class
+} )
+@SessionFactory
+@JiraKey("HHH-17102")
+public class InheritanceTests {
+
+	@BeforeEach
+	public void prepareData(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.save( new Child( 1L, "test", 123 ) );
+				}
+		);
+	}
+
+	@AfterEach
+	public void cleanUpData(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.createQuery( "delete Child" ).executeUpdate();
+				}
+		);
+	}
+
+	@Test
+	public void testResultSetMappingForParentEntity(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					final List<Parent> children = session.createNamedQuery( "Parent", Parent.class ).getResultList();
+					assertEquals( 1, children.size() );
+					assertEquals( 1L, children.get( 0 ).id );
+					assertEquals( "test", children.get( 0 ).name );
+					assertInstanceOf( Child.class, children.get( 0 ) );
+					assertEquals( 123, ( (Child) children.get( 0 ) ).test );
+				}
+		);
+	}
+
+	@Test
+	public void testResultSetMappingForChildEntity(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					final List<Child> children = session.createNamedQuery( "Child", Child.class ).getResultList();
+					assertEquals( 1, children.size() );
+					assertEquals( 1L, children.get( 0 ).id );
+					assertEquals( "test", children.get( 0 ).name );
+					assertEquals( 123, children.get( 0 ).test );
+				}
+		);
+	}
+
+	@SqlResultSetMapping(
+			name = "ParentResult",
+			entities = {
+					@EntityResult(
+							entityClass = Parent.class,
+							discriminatorColumn = "discr",
+							fields = {
+									@FieldResult(name = "id", column = "id"),
+									@FieldResult(name = "name", column = "name"),
+									@FieldResult(name = "test", column = "test")
+							}
+					)
+			}
+	)
+	@NamedNativeQuery(
+			name = "Parent",
+			query = "SELECT p.id as id, case when c.id is not null then 1 else 0 end as discr, p.name as name, c.test as test FROM parent p left join child c on p.id = c.id",
+			resultSetMapping = "ParentResult"
+	)
+	@Entity(name = "Parent")
+	@Table(name = "parent")
+	@Inheritance(strategy = InheritanceType.JOINED)
+	public static class Parent {
+		@Id
+		@Column(name = "id")
+		Long id;
+		String name;
+
+		public Parent() {
+		}
+
+		public Parent(Long id, String name) {
+			this.id = id;
+			this.name = name;
+		}
+	}
+
+	@SqlResultSetMapping(
+			name = "ChildResult",
+			entities = {
+					@EntityResult(
+							entityClass = Child.class,
+							fields = {
+									@FieldResult(name = "id", column = "id"),
+									@FieldResult(name = "name", column = "name"),
+									@FieldResult(name = "test", column = "test")
+							}
+					)
+			}
+	)
+	@NamedNativeQuery(
+			name = "Child",
+			query = "SELECT c.id as id, 'test' as name, c.test FROM child c",
+			resultSetMapping = "ChildResult"
+	)
+	@Entity(name = "Child")
+	@Table(name = "child")
+	public static class Child extends Parent {
+		@Column(name = "test")
+		int test;
+
+		public Child() {
+		}
+
+		public Child(Long id, String name, int test) {
+			super( id, name );
+			this.test = test;
+		}
+	}
+}