Testcase for CriteriaQuery for Sum of Case/When/then using Enumeration - Hibernate only

orm/hibernate-orm-6/src/test/java/org/hibernate/bugs/JPAUnitTestCase.java

@@ -1,5 +1,10 @@
 package org.hibernate.bugs;
 
+import jakarta.persistence.criteria.CriteriaBuilder;
+import jakarta.persistence.criteria.CriteriaQuery;
+import jakarta.persistence.criteria.Root;
+import jakarta.persistence.criteria.Selection;
+import java.util.List;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -31,7 +36,29 @@ void destroy() {
 	void hhh123Test() throws Exception {
 		EntityManager entityManager = entityManagerFactory.createEntityManager();
 		entityManager.getTransaction().begin();
-		// Do stuff...
+
+		CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
+
+		CriteriaQuery<OurEntityPercentageStatus> criteriaQuery = criteriaBuilder.createQuery(OurEntityPercentageStatus.class);
+		Root<OurEntity> root = criteriaQuery.from(OurEntity.class);
+		criteriaQuery.groupBy(root.get("commonName"));
+
+		OurStatus ourStatus = OurStatus.STATUS_1;
+
+		// Get percentage of ourEntities in status STATUS_1. PSEUDOCODE: SUM(case when our_status == STATUS_1 then 1 else 0 end) / cast(Count(*) as decimal)) * 100  as percentage_out
+		Selection<Double> percentageOutSelection = criteriaBuilder.prod(criteriaBuilder.quot(criteriaBuilder.sum(
+			criteriaBuilder.selectCase(root.get("ourStatus"))
+				.when(ourStatus.ordinal(), 1.0)
+				.otherwise(0.0)
+				.as(Double.class)), criteriaBuilder.count(root)), 100.0).as(Double.class).alias("percentage_out");
+
+		//Get objects with dealerDatabaseId and percentage_out
+		criteriaQuery.select(
+			criteriaBuilder.construct(OurEntityPercentageStatus.class, root.get("commonName"), percentageOutSelection));
+		CriteriaQuery<OurEntityPercentageStatus> finalQuery = criteriaQuery.multiselect(root.get("commonName"),
+			percentageOutSelection);
+		List<OurEntityPercentageStatus> resultList = entityManager.createQuery(finalQuery).getResultList();
+
 		entityManager.getTransaction().commit();
 		entityManager.close();
 	}

orm/hibernate-orm-6/src/test/java/org/hibernate/bugs/OurEntity.java

@@ -0,0 +1,56 @@
+package org.hibernate.bugs;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.SequenceGenerator;
+
+@Entity
+public class OurEntity {
+
+    @Id
+    @SequenceGenerator(name = "ourEntitySeq", sequenceName = "OUR_ENTITY_ID_SEQ", allocationSize = 1)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "ourEntitySeq")
+    private Long id;
+    @Column(name = "name")
+    private String name;
+
+    @Column(name = "common_name")
+    private String commonName;
+    @Column(name = "our_status")
+    private OurStatus ourStatus;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getCommonName() {
+        return commonName;
+    }
+
+    public void setCommonName(String common_name) {
+        this.commonName = common_name;
+    }
+
+    public OurStatus getOurStatus() {
+        return ourStatus;
+    }
+
+    public void setOurStatus(OurStatus ourStatus) {
+        this.ourStatus = ourStatus;
+    }
+}

orm/hibernate-orm-6/src/test/java/org/hibernate/bugs/OurEntityPercentageStatus.java

@@ -0,0 +1,28 @@
+package org.hibernate.bugs;
+
+public class OurEntityPercentageStatus {
+
+    private String commonName;
+    private Double percentageStatus;
+
+    public OurEntityPercentageStatus(String commonName, Double percentageStatus) {
+        this.commonName = commonName;
+        this.percentageStatus = percentageStatus;
+    }
+
+    public String getCommonName() {
+        return commonName;
+    }
+
+    public void setCommonName(String commonName) {
+        this.commonName = commonName;
+    }
+
+    public Double getPercentageOut() {
+        return percentageStatus;
+    }
+
+    public void setPercentageOut(Double percentageOut) {
+        this.percentageStatus = percentageOut;
+    }
+}

orm/hibernate-orm-6/src/test/java/org/hibernate/bugs/OurStatus.java

@@ -0,0 +1,7 @@
+package org.hibernate.bugs;
+
+public enum OurStatus {
+    STATUS_1,
+    STATUS_2,
+    ;
+}

orm/hibernate-orm-6/src/test/resources/hibernate.properties

@@ -5,7 +5,7 @@
 # See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 #
 
-hibernate.dialect org.hibernate.dialect.H2Dialect
+hibernate.dialect org.hibernate.dialect.PostgreSQLDialect
 hibernate.connection.driver_class org.h2.Driver
 #hibernate.connection.url jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1;MVCC=TRUE
 hibernate.connection.url jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1
@@ -14,7 +14,7 @@ hibernate.connection.password
 
 hibernate.connection.pool_size 5
 
-hibernate.show_sql false
+hibernate.show_sql true
 hibernate.format_sql true
 
 hibernate.max_fetch_depth 5
@@ -27,4 +27,4 @@ hibernate.jdbc.batch_versioned_data true
 
 jakarta.persistence.validation.mode=NONE
 hibernate.service.allow_crawling=false
-hibernate.session.events.log=true
+hibernate.session.events.log=true