HHH-19974 Use columnDefinition for null casting

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/InformixDialect.java

@@ -40,6 +40,7 @@
 import org.hibernate.exception.LockAcquisitionException;
 import org.hibernate.exception.spi.SQLExceptionConversionDelegate;
 import org.hibernate.mapping.CheckConstraint;
+import org.hibernate.metamodel.mapping.SqlTypedMapping;
 import org.hibernate.query.sqm.CastType;
 import org.hibernate.query.sqm.IntervalType;
 import org.hibernate.query.sqm.function.SqmFunctionRegistry;
@@ -1097,6 +1098,18 @@ public String getSelectClauseNullString(int sqlType, TypeConfiguration typeConfi
 return "cast(null as " + castType + ")";
 }
 
+//	Add override for the newer signature to access columnDefinition
+@Override
+public String getSelectClauseNullString(SqlTypedMapping sqlType, TypeConfiguration typeConfiguration) {
+final String castTypeName = sqlType.getColumnDefinition();
+if ( castTypeName != null ) {
+return "cast(null as " + castTypeName + ")";
+}
+
+return getSelectClauseNullString( sqlType.getJdbcMapping().getJdbcType().getDdlTypeCode(), typeConfiguration );
+}
+
+
 private static String castType(DdlType descriptor) {
 final String typeName = descriptor.getTypeName( Size.length( Size.DEFAULT_LENGTH ) );
 //trim off the length/precision/scale

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/PostgreSQLLegacyDialect.java

@@ -962,9 +962,18 @@ public String getSelectClauseNullString(int sqlType, TypeConfiguration typeConfi
 
 @Override
 public String getSelectClauseNullString(SqlTypedMapping sqlType, TypeConfiguration typeConfiguration) {
-final String castTypeName = typeConfiguration.getDdlTypeRegistry()
-.getDescriptor( sqlType.getJdbcMapping().getJdbcType().getDdlTypeCode() )
-.getCastTypeName( sqlType.toSize(), (SqlExpressible) sqlType.getJdbcMapping(), typeConfiguration.getDdlTypeRegistry() );
+String castTypeName = sqlType.getColumnDefinition();
+
+if ( castTypeName == null ) {
+castTypeName = typeConfiguration.getDdlTypeRegistry()
+.getDescriptor( sqlType.getJdbcMapping().getJdbcType().getDdlTypeCode() )
+.getCastTypeName(
+sqlType.toSize(),
+(SqlExpressible) sqlType.getJdbcMapping(),
+typeConfiguration.getDdlTypeRegistry()
+);
+}
+
 return "cast(null as " + castTypeName + ")";
 }
 

hibernate-community-dialects/src/test/java/org/hibernate/community/dialect/PostgreSQLLegacyDialectTest.java

@@ -0,0 +1,130 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.community.dialect;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.resource.jdbc.spi.StatementInspector;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.RequiresDialect;
+import org.hibernate.testing.orm.junit.ServiceRegistry;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.hibernate.testing.orm.junit.Setting;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.Inheritance;
+import jakarta.persistence.InheritanceType;
+
+// Even though we are testing PostgreSQLLegacyDialect, the test environment runs a standard PostgreSQL instance,
+// which is detected as PostgreSQLDialect. To prevent the test from being skipped, we require PostgreSQLDialect.
+// The actual PostgreSQLLegacyDialect is enforced internally via the @Setting annotation.
+@RequiresDialect(org.hibernate.dialect.PostgreSQLDialect.class)
+@DomainModel(annotatedClasses = {
+PostgreSQLLegacyDialectTest.BaseEntity.class,
+PostgreSQLLegacyDialectTest.InetEntity.class,
+PostgreSQLLegacyDialectTest.EmptyEntity.class
+})
+@SessionFactory
+@ServiceRegistry(
+settings = {
+@Setting(
+name = AvailableSettings.DIALECT,
+value = "org.hibernate.community.dialect.PostgreSQLLegacyDialect"
+),
+@Setting(
+name = AvailableSettings.STATEMENT_INSPECTOR,
+value = "org.hibernate.community.dialect.PostgreSQLLegacyDialectTest$SqlSpy"
+)
+}
+
+)
+public class PostgreSQLLegacyDialectTest {
+
+public static final List<String> SQL_LOG = new ArrayList<>();
+
+@BeforeEach
+protected void setupTest(SessionFactoryScope scope) {
+SQL_LOG.clear();
+scope.inTransaction(
+(session) -> {
+session.createNativeQuery(
+"insert " +
+"into inet_entity (id, ipAddress) " +
+"values (1, '192.168.0.1'::inet)"
+)
+.executeUpdate();
+session.persist( new EmptyEntity() );
+}
+);
+SQL_LOG.clear();
+}
+
+@Test
+@JiraKey(value = "HHH-19974")
+public void testCastNullString(SessionFactoryScope scope) {
+scope.inTransaction(
+(session) -> {
+String entityName = BaseEntity.class.getName();
+
+List<BaseEntity> results = session.createQuery(
+"select r from " + entityName + " r", BaseEntity.class
+).list();
+
+boolean foundCast = false;
+for ( String sql : SQL_LOG ) {
+if ( sql.contains( "cast(null as inet)" ) ) {
+foundCast = true;
+break;
+}
+}
+
+Assertions.assertTrue( foundCast, "must contains 'cast(null as inet)' clause." );
+}
+);
+}
+
+
+@Entity(name = "root_entity")
+@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+public static abstract class BaseEntity {
+@Id
+@GeneratedValue
+private Long id;
+}
+
+@Entity(name = "inet_entity")
+public static class InetEntity extends BaseEntity {
+
+@Column(columnDefinition = "inet")
+private String ipAddress;
+
+public InetEntity() {
+}
+}
+
+@Entity(name = "empty_entity")
+public static class EmptyEntity extends BaseEntity {
+}
+
+public static class SqlSpy implements StatementInspector {
+@Override
+public String inspect(String sql) {
+SQL_LOG.add( sql.toLowerCase() );
+return sql;
+}
+}
+
+}

hibernate-core/src/main/java/org/hibernate/dialect/PostgreSQLDialect.java

@@ -944,12 +944,16 @@ public String getSelectClauseNullString(int sqlType, TypeConfiguration typeConfi
 
 @Override
 public String getSelectClauseNullString(SqlTypedMapping sqlType, TypeConfiguration typeConfiguration) {
-final DdlTypeRegistry ddlTypeRegistry = typeConfiguration.getDdlTypeRegistry();
-final String castTypeName = ddlTypeRegistry
-.getDescriptor( sqlType.getJdbcMapping().getJdbcType().getDdlTypeCode() )
-.getCastTypeName( sqlType.toSize(), (SqlExpressible) sqlType.getJdbcMapping(), ddlTypeRegistry );
-// PostgreSQL assumes a plain null literal in the select statement to be of type text,
-// which can lead to issues in e.g. the union subclass strategy, so do a cast
+String castTypeName = sqlType.getColumnDefinition();
+
+if ( castTypeName == null ) {
+final DdlTypeRegistry ddlTypeRegistry = typeConfiguration.getDdlTypeRegistry();
+castTypeName = ddlTypeRegistry
+.getDescriptor( sqlType.getJdbcMapping().getJdbcType().getDdlTypeCode() )
+.getCastTypeName( sqlType.toSize(), (SqlExpressible) sqlType.getJdbcMapping(), ddlTypeRegistry );
+// PostgreSQL assumes a plain null literal in the select statement to be of type text,
+// which can lead to issues in e.g. the union subclass strategy, so do a cast
+}
 return "cast(null as " + castTypeName + ")";
 }
 

hibernate-core/src/test/java/org/hibernate/dialect/PostgreSQLDialectTest.java

@@ -0,0 +1,121 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.dialect;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.resource.jdbc.spi.StatementInspector;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.RequiresDialect;
+import org.hibernate.testing.orm.junit.ServiceRegistry;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.hibernate.testing.orm.junit.Setting;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.Inheritance;
+import jakarta.persistence.InheritanceType;
+
+@RequiresDialect(PostgreSQLDialect.class)
+@DomainModel(annotatedClasses = {
+PostgreSQLDialectTest.BaseEntity.class,
+PostgreSQLDialectTest.InetEntity.class,
+PostgreSQLDialectTest.EmptyEntity.class
+})
+@SessionFactory
+@ServiceRegistry(
+settings = @Setting(
+name = AvailableSettings.STATEMENT_INSPECTOR,
+value = "org.hibernate.dialect.PostgreSQLDialectTest$SqlSpy"
+)
+)
+public class PostgreSQLDialectTest {
+
+public static final List<String> SQL_LOG = new ArrayList<>();
+
+@BeforeEach
+protected void setupTest(SessionFactoryScope scope) {
+SQL_LOG.clear();
+scope.inTransaction(
+(session) -> {
+session.createNativeQuery(
+"insert " +
+"into inet_entity (id, ipAddress) " +
+"values (1, '192.168.0.1'::inet)"
+)
+.executeUpdate();
+session.persist( new EmptyEntity() );
+}
+);
+SQL_LOG.clear();
+}
+
+@Test
+@JiraKey(value = "HHH-19974")
+public void testCastNullString(SessionFactoryScope scope) {
+scope.inTransaction(
+(session) -> {
+String entityName = BaseEntity.class.getName();
+
+List<BaseEntity> results = session.createQuery(
+"select r from " + entityName + " r", BaseEntity.class
+).list();
+
+boolean foundCast = false;
+for ( String sql : SQL_LOG ) {
+if ( sql.contains( "cast(null as inet)" ) ) {
+foundCast = true;
+break;
+}
+}
+
+Assertions.assertTrue( foundCast, "must contains 'cast(null as inet)' clause." );
+}
+);
+}
+
+
+@Entity(name = "root_entity")
+@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+public static abstract class BaseEntity {
+@Id
+@GeneratedValue
+private Long id;
+}
+
+@Entity(name = "inet_entity")
+public static class InetEntity extends BaseEntity {
+
+@Column(columnDefinition = "inet")
+private String ipAddress;
+
+public InetEntity() {
+}
+}
+
+@Entity(name = "empty_entity")
+public static class EmptyEntity extends BaseEntity {
+}
+
+public static class SqlSpy implements StatementInspector {
+@Override
+public String inspect(String sql) {
+SQL_LOG.add( sql.toLowerCase() );
+return sql;
+}
+}
+
+}