From 052552f3f6077ffa6040c25c8496ddc1e86b37c4 Mon Sep 17 00:00:00 2001
From: Andrea Boriero <andrea@hibernate.org>
Date: Tue, 17 Sep 2024 15:32:09 +0200
Subject: [PATCH] HHH-18515 Unrecognized discriminator value exception when
 running native query on entity with discriminator column

---
 .../mapping/MappedDiscriminatorConverter.java | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/hibernate-core/src/main/java/org/hibernate/metamodel/mapping/MappedDiscriminatorConverter.java b/hibernate-core/src/main/java/org/hibernate/metamodel/mapping/MappedDiscriminatorConverter.java
index 040ecf2c05..c6fffadb5d 100644
--- a/hibernate-core/src/main/java/org/hibernate/metamodel/mapping/MappedDiscriminatorConverter.java
+++ b/hibernate-core/src/main/java/org/hibernate/metamodel/mapping/MappedDiscriminatorConverter.java
@@ -11,7 +11,9 @@ import org.hibernate.metamodel.mapping.internal.DiscriminatorValueDetailsImpl;
 import org.hibernate.metamodel.model.domain.NavigableRole;
 import org.hibernate.metamodel.spi.MappingMetamodelImplementor;
 import org.hibernate.type.BasicType;
+import org.hibernate.type.descriptor.java.CharacterJavaType;
 import org.hibernate.type.descriptor.java.JavaType;
+import org.hibernate.type.descriptor.java.StringJavaType;
 
 import java.util.List;
 import java.util.Map;
@@ -111,6 +113,23 @@ public class MappedDiscriminatorConverter<O,R> extends DiscriminatorConverter<O,
 			return notNullMatch;
 		}
 
+		if ( value.getClass().isEnum() ) {
+			final Object enumValue;
+			if ( getRelationalJavaType() instanceof StringJavaType ) {
+				enumValue = ( (Enum) value ).name();
+			}
+			else if ( getRelationalJavaType() instanceof CharacterJavaType ) {
+				enumValue = ( (Enum) value ).name().charAt( 0 );
+			}
+			else {
+				enumValue = ( (Enum) value ).ordinal();
+			}
+			final DiscriminatorValueDetails enumMatch = discriminatorValueToEntityNameMap.get( enumValue );
+			if ( enumMatch != null ) {
+				return enumMatch;
+			}
+		}
+
 		throw new HibernateException( "Unrecognized discriminator value: " + value );
 	}